Almost Kiss: Tony and Pepper during the Stark charity event.
Alone in a Crowd: After Obadiah reveals that he had the board file an injunction (a legal order restricting Tony's power over Stark Industries) against Tony.
Amusing Injuries: Tony sets the suit's thrusters to ten percent power, and is slammed against the ceiling hard enough that, realistically, he should have broken at least a few bones... from that or from the subsequent face-first fall on the floor.
Then, there's the scene when Tony's assistant, Pepper Potts, walks into his lab just as he's testing one of the repulsor beams in the suit's gloves. The recoil throws Tony offscreen and you hear him hit the far wall a couple seconds later. Pepper's reaction, mainly her complete lack of concern for his safety, is what really sells it.
And Show It to You / Beat Still, My Heart: A variation. Obadiah toys with Tony's new arc reactor right in front of him after yanking it out. It wasn't actually his heart, but the reactor kept his heart from failing.
Benevolent A.I.: All of Tony's AI creations, from JARVIS to the armature robot, Dummy, are not only extremely helpful, but extremely affable too.
Tony Stark: (looking at a solid gold render of his armor) A little ostentatious, don't you think? JARVIS: What was I thinking? You're usually so discreet. Tony Stark: Tell you what. Throw a little hotrod red in there. JARVIS: Yes, that should help you keep a low profile.
For another example, the mobile robotic arm he built when he was a child behaves exactly like a faithful dog. During one of the climactic scenes, Tony is dying, and needs to reach the spare arc reactor to put into his chest, but can't reach it. Tony crumples to the ground, about to die, when the robotic arm suddenly fetches it for him, and even whimpers like a dog concerned about his owner. Tony smiles and says "Good boy," and takes the arc reactor. The same robotic arm also shows up in the sequel, although in a somewhat smaller role. Needless to say, he's the closest thing Tony has to an actual pet.
The arm he uses to operate as a fire extinguisher while testing his suit technology is a bit of a crapshoot. It can't seem to figure out when the right time is to spray Tony. He gets sprayed once while not on fire and has to ward it off from spraying him numerous times in the scene where he perfects the rockets.
Bigger Stick: Everyone from the Ten Rings to Obadiah Stane wants to get their hands on Tony's Iron Man technology so they can outstrip everyone else's weapons. The phrase "bigger stick" even comes up in the movie itself when Tony is talking to the reporter about his father. "Peace means having a bigger stick than the other guy."
Bilingual Bonus: If you speak Urdu, you know Stane was behind Tony's kidnapping an hour before Pepper translates the ransom tape.
Black Market: Stane, the VP of Tony's company has been selling weapons to the Ten Rings organization behind Tony's back.
Tony Stark builds a electromagnetic device called an Arc Reactor to protect his heart, then upgrades the unit by having his secretary, Pepper, install a larger version in his chest. He tells her to throw the small unit away, but Pepper has it put in a display case for him. The miniature reactor becomes crucial later on, when Obadiah Stane takes the larger reactor from Tony's chest while he's paralyzed, and he must rely on the smaller model to power his suit and his heart.
Tony's second attempt at the suit doesn't work out too well after ice builds up during a high-atmosphere flight. He later uses this against the Big Bad.
The giant Arc-Reactor which is mentioned in the first third of the movie, then overloaded at the end to finally defeat Obadiah Stane.
Chekhov's Skill: Tony Stark is testing his Mk. II armor's flight capabilities, and decides to break the altitude record, just because. He fails because the suit builds up a layer of ice which shorts out its systems; Tony later Hand Waves a fix for this. Later in the movie, he lures the Big Bad Iron Monger to similar altitudes, causing Iron Monger's suit to freeze up while his own suit is protected.
Chest Blaster: Tony uses this during the climax to blast Iron Monger out from under the car he's holding. It's one of the extremely few appearances in the films of the Unibeam; in the comics, Iron Man's chest plate can project not only a searchlight but various kinds of energy. When Iron Man really needs to blast someone or something, the Unibeam fires a super-sized repulsor ray.
Chronic Backstabbing Disorder: Stane plotted from the beginning of the movie to eliminate Tony so he could seize the company and engage in any sort of weapon deals he wanted. However, he also turns his back on the terrorists who he was paying later in the film to get his hands on the Mk. 1 suit they recovered from the desert. They had mildly backstabbed him also when they learned their captive was Tony Stark, causing them to keep him alive so he could build them a missile instead of killing him like their orders.
The Coroner Doth Protest Too Much: Coulson states that S.H.I.E.L.D. is going to provide a heroic example of that - Obadiah Stane is currently on vacation, taking a very unsafe vehicle.
Curb-Stomp Battle: Tony Stark's Power Suit vs. a group of terrorists armed with powerful automatic weapons, grenade launchers, and tanks = easy Stark victory in under 6 full minutes. The more he upgrades the armor, the more epic the curb-stomp.
Dance of Romance: Tony only notices Pepper romantically when he gets her out onto the dance floor.
The Darkness Gazes Back: In the finale, Pepper Potts and agents of SHIELD are looking for Big Bad Obadiah Stane in his darkly-lit workshop. Pepper notices a suspiciously-large shadow and cautiously stares into it, only for the Iron Monger to power up and two glowing mechanical eyes to stare back at her.
Evil Plan: Raza, a Ten Rings officier, wants to become a modern Ghengis Khan and plans to use Stark Industries technology to accomplish this. He's actually The Dragon for the true big bad, Stane, who planned to use Raza to kill Tony and take over Stark Industries.
Expecting Someone Taller: Pepper, Coulson, and his men enter Sector 16 and find Tony's original suit, mistaking it for Stane's power armor. Pepper remarks, "I thought it'd be bigger". It is!
Five Rounds Rapid: When Iron Monger powers up in the midst of them, the S.H.I.E.L.D. agents immediately all start shooting at it with their sidearms. Needless to say, they get owned in short order.
Floorboard Failure: Tony's first flight test ends with him crashing though his ceiling and the floor during an attempted landing. Further casualties are a piano and a car. Followed shortly thereafter by what little remains of Tony's dignity when his Robot Buddy Dummy blasts him in the face with a fire extinguisher. Again.
Going Critical: Just as the trope description says, calling anything a reactor is a sheer sign that it's going to blow up before the movie's done. Stark Industries is powered by an Arc Reactor. In the climax, guess what it does.
Heel-Face Turn: Tony sums up his new change in direction to Obadiah when he chews him out for shutting down the weapons division of Stark Industries;
Tony: We're not doing good enough, we can do better, we can do something else.
Hero For A Day: The villain powers his own version of the power suit by stealing Stark's portable generator, leaving Stark literally powerless for a short while.
Hey, Wait!: "Is that today's paper?" This is a exploitation of the trope. Obadiah suspects Pepper is up to something the moment he enters the office. He only asks for the paper because he (correctly) thinks she's hiding something in it. He doesn't care about the paper, he throws it down onto the desk as soon as she leaves.
High Up Ice Up: Nearly gets him killed while he's testing the suit, but then proves useful against Obadiah Stane.
How Do I Shot Web?: The first half of the film is Tony trying to figure out how to fly. The Mark I armor doesn't so much fly as rocket skyward and then fall, and after building his boot jets for the Mark II armor, Tony invents the repulsors to act as flight stabilizers and then after that, there's the icing problem.
Idiot Ball: The S.H.I.E.L.D agents, first ignoring the more advanced suit on the computer monitor and then trying to shoot at Iron Monger with handguns.
I Just Shot Marvin in the Face: The Ten Rings terrorists waffle between proper trigger discipline while lounging around their base to rather stark disregard for gun safety during their video transmission of their demands.
Icarus Allusion: Tony flies toward the moon because he can and ice builds up on his suit. He later solves this problem and uses it to his advantage against an enemy.
Impossible Task Instantly Accomplished: Tony Stark is captured by would-be conquerors, and forced to build a Jericho Missile (which he designed) within a week or so or the battery powering his new "pacemaker" will die. Within that week, he instead designs a miniature arc reactor, builds it, installs it to power his heart, then designs a suit of Powered Armor, builds that, and escapes... just as the terrorists were growing suspicious.
Improv: According toJeff Bridges, there was no script; the entire movie was improvised. Bridges said he had problems getting his head around this style of film making until he told himself to think of it as "a $200 million student film". In an interview, director Jon Favreau confirmed that there was no completed script, and wrote and rewrote many scenes during production. Also while most of the dialogue scenes were improvised, the action scenes were thoroughly planned out. Lastly, all of the changes got approval by Marvel studio executives along the way. Think about that. A near-total improvisation movie is one of the most highly rated movies ever (95% on the Tomato Meter; more than half of the PIXAR movies out there) and grossed well over $585 million worldwide.
In Medias Res: The movie begins a little while in with Tony in Afghanistan being escorted back to his plane. He jokes around with the troops then his convoy gets attacked. His guards are quickly slaughtered and when he tries to take cover. A missile, one made by his company, lands near him and explodes in his face knocking him unconscious. Tony's then captured by the Ten Rings and is put up for ransom. The story then flashes back 36 hours to show Tony's personal life up till that point.
Insistent Terminology: Tony Stark is the lone civilian riding in a Humvee in Afghanistan. He asks the driver whether it's appropriate to call her a "Soldier" or if there is a prefered nomenclature since she's female. She points out that the correct nomenclature is Airman, because she is in the US Air Force.
Irony: Much of the underlying plot of the film is tragic irony, as pointed out by Stane:
"How ironic, Tony! Trying to rid the world of weapons, you gave it its best one ever!"
It's Personal: Tony decides to go back to Afghanistan and take on the Ten Rings after seeing they've attacked Yinsen's hometown. This is his debut as Iron Man.
Join or Die: This is how the Ten Rings recruits. They attack villages and either kill or capture the men. Then, they take their women and children to an unknown location where they're used as collateral. The men are asked to join them, with their families' lives, as well as their own, on their line if they refuse. This is Truth in Television for many terrorist groups and militaristic regimes.
Karmic Death: Stane belittled the arc reactor they'd constructed before, so it's appropriate that he dies falling into the same reactor after being electrocuted by it.
Lampshade Hanging: Tony's little speech about the "realities" of being a superhero right before his press conference at the end.
Literal Change of Heart: Sort of. Getting the Arc Reactor installed in Tony's chest symbolically represents his assumption of the role of Iron Man.
Living Legend: Tony's jealous of his own coverage and outs himself as The Iron Man.
Locking MacGyver in the Store Cupboard: The terrorists holding him hostage literally gave Tony everything he needed to build the first Iron Man suit and escape. This movie is the page image for a reason.
Look Ma, No Plane!: The "fight military aircraft" version (though he never actually attacks them; the only damage to a plane comes from accidentally colliding with him).
Made Of Titanium: Literally. The Iron Man Powered Armor is made of a "gold-titanium alloy". Why? To correct a design flaw that the previous iteration's steel casing had that only manifests in specific circumstances... and because he can.
Mauve Shirt: The soldiers escorting Tony at the start of the film received a few fleeting minutes of characterization before they were wiped out by Stark's captors.
Robert Downey, Jr. was cast almost specifically because he is a gifted actor who's had drugs problems in the past. He's portraying a gifted scientist and businessman who lives fast and can never seem to put the bottle down.
Jeff Bridges is also a great choice to play the villain, because it's a role he doesn't normally play. He comes across as friendly and likeable, albeit a bit of a smooth talker. And when we learn he was behind everything, we empathize with the betrayal Tony is feeling, because we're feeling it as well.
Tony helped to design and build many of the weapons being used by the Ten Rings.
Iron Man unintentionally causes the destruction of an Air Force F-22 that attempted to intercept him (before they knew he was a good guy). In his defense, he made sure that the pilot's ejection suit worked properly.
Noodle Incident: JARVIS is removing Tony's armor, their dialogue is loaded with Innocent Innuedo and Pepper walks in. Tony says the following "...Let's face it, this is not the worst thing you've caught me doing."
No Plans, No Prototype, No Backup: Avoided in every way the writers could think of. The first suit and its plans are recovered and used as a basis for Stane's. Stark has two functional suits in his house, and the facilities to build a new one from scratch in five hours... If not for Pepper's leaving the original mini-Arc Reactor as a gift to Tony, Obadiah would have successfully left Tony for dead.
Not a Game: Rhodey says something to this extent to Tony during their phone conversationwhile Tony is in the middle of evading a pair of F-22 Raptors over Gulmira.
Oh Crap: Obadiah's reaction when Tony points out the following design flaw.
Tony: How'd you solve the icing problem? Obadiah:...Icing problem? *Suit cuts out* Tony: *Smugly* Might want to look into it!
Omniscient Database: Variant; when Pepper Potts is hacking the Stark Industries mainframe from Stark's office computer (and at his request), she instantly translates the soundtrack of a foreign language video into (appropriately accented!) English by typing in "Translate" on the video viewer's window. This is a case of Shown Their Work - New Scientist checked up the plausibility of this and found that there are programs in development that do the same thing, if not quite so smoothly just yet, but there's no excuse for the accent.
There was a scene planned for the climax of the first film where Iron Man drives his Audi into Iron Monger, where it flips and he breaks the roof in half and jumps out. The effects team found that A) the car was too well-engineered to flip, and B) the roof was too difficult to cut through. The entire scene was scrapped. Yes, that's right, the Product Placement car was (in a sense) Too Awesome to Use.
The unfinished version of this scene can be found on the DVD and, hilariously enough, it references the above flaw: the first thing Tony says to Rhodes is "Did you flip it?", to which Rhodey incredulously responds "No I didn't flip it!"
Released to Elsewhere: The Ten Rings promise to let Tony go after he has finished building the Jericho missile.
Sexy Backless Outfit: Pepper's dress at a party. She feels distinctly uncomfortable in it, to say nothing of the fact that she forgot to put on deodorant and is dancing with her boss in front of her co-workers. Tony tries to put her at ease by telling her she smells fine.
At the end of the movie, Tony Stark and S.H.I.E.L.D. had earlier come up with a cover story that Tony was supposed to give at the press conference. After a few questions from a skeptical press, Tony decides to just tell the truth: "I am Iron Man."
Also, assuming the movie had a script, something like this happened during shooting. This is the case according to Favreau, Bridges, and Downey.
Trailers Always Spoil: Paramount marketing put this movie on a heavy trailer rotation for a clean month before the US release, allowing a lot of people to figure out many of the plot elements.
Travelling at the Speed of Plot: Either that, or Tony Stark is so good at seducing women, he can infatuate the reporter at the beginning of the movie enough to make her drive four and a half hours from Las Vegas to Malibu just to have sex with him.
Treacherous Advisor: Obadiah Stane, a major villain from the comics who drove Tony into alcoholism and took over his company, before Stark sobered up and defeated him, is retooled as having co-founded Stark Industries with Tony's dad, then serves as a mentor to Tony and the second-in-command of his company when the elder Stark dies and Tony inherits the company. Naturally, this being an adaptation, Obadiah turns out to be more villainous than he lets on.
Trespassing To Talk: At the end of the film, Nick Fury breaks into Tony Stark's house to talk to him about the Avengers Initiative.
Twist Ending: Most superhero movies end with the hero's Secret Identity intact, but at the end of the first film, Stark reveals it to the world. This is even after the comic book "bodyguard" explanation is devised as a cover... which is then torn apart by another character who remarks on how ridiculous it is. Considering Stark's humanitarian ways, this makes a great deal of sense.
Unflinching Walk: Iron Man fires a remote explosive at a tank in Afghanistan then calmly walks away. A few seconds later it detonates and takes the tank with it.
Upgrade vs. Prototype Fight: The film has a sort-of example: The Iron Monger suit is based off research from the original Mark I armor, and is certainly larger and more powerful than Tony's. The latter's Mark III is also an upgrade, but is weaker because it's using the Mark I's old arc reactor.
Viewer-Friendly Interface: Most of the images inside the Iron Man suit's holographic interface are so large that they would obstruct Tony's view, display data he doesn't need at that time, and generally are there more to look cool for the viewer than be useful to Tony.
Villainous Breakdown: Obadiah Stane, after finding out no one but Tony knows how to make a miniaturized arc reactor.
Stane:TONY STARK WAS ABLE TO BUILD THIS IN A CAVE! WITH A BOX OF SCRAPS!!'
The War on Terror: Part of the movie is set in Afghanistan as the American military battles guerrilla fighters hiding out in caves, obviously influenced by the War on Terror. However, the antagonists have been changed from Afghan Islamic extremists to a multinational, multilingual, foreign militia called the Ten Rings. The Ten Rings has no explicit religion and a more generic "Take Over the World" raison d'etre.
Weaponized Exhaust: Tony's repulsor beams started as high powered exhaust emitted by his prototype suit's flight system.
Before that, the repulsor was the engine for the new Jericho missile.
Wham Line: The ending. "Truth is... I am Iron Man."
What the Hell, Hero?: A variation, as Tony calls Pepper out for walking out now that he wants to protect everyone he's put in danger, whereas before she had no problem with his reaping the benefits of destruction.
What The Hell, Townspeople?: Iron Man saves a mother and kids driving a car from smashing into the ground after they're thrown by Iron Monger. Their response? They start screaming and run Tony over as they drive away.
When Things Spin, Science Happens: When the outer breastplate is closed during the Mark III suiting-up sequence, the structures surrounding the arc reactor spin counter-clockwise ever so slightly.
Worf Had The Flu: Tony is forced to use his original arc reactor after Stane steals the improved reactor, which isn't powerful enough for his improved suit.