Always Save the Girl: Averted. Brahmwell decides to cut down the beanstalk to save the kingdom, even if it means his daughter will be left trapped with the Giants
A Minor Kidroduction: Jack and Isabelle are introduced to us as kids being read a bed time story about giants.
Ax Crazy: Wicke comes off as just slightly unhinged during a lot of his screen time. Whenever Roderick gives him the cue to either kill someone or that he's going to do it himself, he reacts with glee and excitement, and even when that's not happening, he's usually trembling and/or smiling eagerly about doing whatever it is they're planning to do next.
Babies Ever After: The film opens with Jack hearing stories from his mum about the long-ago war with the giants. It ends with Jack and the Princess—now safely married and living in the palace—telling stories of their own adventures to their children.
Big "NO!": Done by Fallon after the beanstalk is chopped down. Fortunately for him, he finds the rest of the beans.
The Cameo: Warwick Davis appears during the beginning of the film. Ian McKellen also makes a vocal cameo in one of the first theatrical trailers reading the quote above, which is also placed in the film's climax in which generations of people tell the story of Jack.
Chekhov's Gun: Jack saved that one last bean... and then uses it to kill Fallon at the climax.
Convection Schmonvection: At one point Elmont is rolled in raw dough and placed in an oven to be cooked as an hors d'oeuvre. When he frees himself a few minutes later, he's not even sweating, despite the fact that the dough he was inside visibly cooked while he was freeing himself.
Cool, but Inefficient: The castle portcullis consists of two metal gates that slide together — which means it takes longer to close, and is much easier to force open, than a normal portcullis.
Deceased Parents Are The Best: Jack's father and Isabelle's mother are both very decent people. Jack's father comforts Jack when's he frightened by a storm. Isabelle's mother encourages her to go on adventures and to be the best she can be.
Disney Villain Death: The giant with the helmet suffers this. Though we do get to see the result of the giant's fall.
The Dragon: Wicke for Roderick and Fumm for Fallon
Evil Is Hammy: Stanley Tucci is in non-stop ham mode as Roderick. For the giants, being hammy is almost a requirement.
Eye Scream: One of the eyeballs in Fallon's miniature head shoots out during his death
Family Unfriendly Death: Fallon has a beanstalk grow from within him, causing his body to burst and send giant chunks of him flying. Also, several humans are either crushed under foot or have their heads bitten off.
Faux Action Girl: Isabelle is brave and adventurous. Despite all this, she is captured by the giants and has to be rescued by Jack all throughout the movie. To her credit, very few of the male characters, apart from Jack, fare any better.
Fire-Forged Friends: At their first meeting, Elmont is not impressed by this bumpkin Jack. After Jack rescues him and Isabelle from being cooked by a giant and they subsequently send another giant plummeting to his death, Elmont gives Jack a King's Guard badge, saying, "You've earned it."
Genre Savvy: Elmont shows a surprising amount of this during his battle with Roderick:
"I may not be the hero of this story, but at least I know how it ends!"
Gory Discretion Shot: The film always cuts away whenever the giants devour the humans, only allowing the viewer to hear the sounds. Averted in the case of Fallon.
Hypocritical Humor: Wicke asks Roderick, after just pushing a soldier to his death, "Why do people always bother screaming before they die?". Ironically, a giant grabs him moments later, and he screams until said giant bites his head off.
Idiot Hero: Jack is a wide-eyed and gullible farmboy who nevertheless grows to be a true hero.
I'm a Humanitarian: Whilst the giants can eat animals, and presumably vegetables, they like human flesh even more and are shown devouring people several times throughout the film.
Logo Joke: The Bad Hat Harry logo has five giants walking in place of five men.
Loophole Abuse: Whoever wears the crown of King Erik controls the giants. However, this does not make them entirely obedient, and they could find ways of killing the wearer of the crown indirectly, or simply standing by and allowing the wearer to be killed.
Mythology Gag: The golden harp from the fairy tale can be seen a handful of times throughout the film.
An egg (though jeweled instead of gold like the tale) can also be seen on the table as Jack is speaking to his children in the final moments of the film. Jack picked it up earlier in the film.
A Mythology Is True: The ending shows that the original fairy tale is based on actual historical fact!
Never Trust a Trailer: The trailers depict the film as being a campy family comedy instead of the dark action film that it really is. It's possible Warner Bros. did this to avoid people claiming that Singer copied the Lord of the Rings series.
Not the Fall That Kills You: Subverted when Jack and Isabelle are on the falling beanstalk; they swing on a smaller vine to convert their downward momentum to horizontal momentum and slide along the ground. Played straight with Elmont on the same beanstalk; he jumps off closer to the ground and lands safely in some Soft Water.
One Gender Race: In the entirety of the film, there is not one single female giant seen. Even in the giant's fortress, its inhabited only by males. Though their fortress being occupied only by males could be justified, since it is most likely a military garrison.
The filmmakers have mentioned in an interview that there was at one point female giants in early stages of the script, but were cut out mainly because the director didn't want to have Jack kill any of them.
Precision F-Strike / Curse Cut Short: Fallon's right head, which is mostly unintelligible, very nearly says the F-word before he explodes after Jack drops a bean down Fallon's throat, causing it to grow from inside him and kill him.
Really 700 Years Old: The giants are long lived, with many being the original invaders during their first invasion of Earth.
Also Elmont, the captain of the Guardians. He'll put a good scare in Jack for not kneeling when he's supposed to—but when the Princess goes missing, Elmont remembers that Jack was the peasant who'd stand up to bullies to protect a strange girl whom he didn't even know was the princess. He vouches for Jack with the King when it counts.
Red Shirt Army: The majority of the guardians who climb up the beanstalk to rescue Isabelle don't even make it up the beanstalk before facing their demise. All the others are killed by the giants quickly. Doesn't help that most of the Guardians are wearing red shirts.
Jack thinks the bullies are really scared of him after he defends the princess. But its the Elmont and the Royal Guardians they're scared of, and he realizes it.
Elmont himself says it when the giant army is about destroy the same Guardians, and they stop for no apparent reason. Jack is behind the Guardians with the Crown. Hence the Ironic Echo.
Royals Who Actually Do Something: King Brahmwell fights alongside his men during the final battle with the giants, joins the soldiers tugging on the lanyards to secure the drawbridge and refuses to flee when things look hopeless.
Elmont: Get the king to safety! King Brahmwell: (pulls out his sword) Like hell!
Sequel Hook: Near the end of the film, set in modern day London, a boy named Rodey grins evilly at the royal crown (actually the crown of King Erik) and carries with him a backpack similar to Roderick's. This heavily implies that he is a descendant of Roderick (or at least a descendant of any siblings or cousins Roderick may have had, as he never had any children himself) and plans to do what his ancestor did centuries ago.
Stupid Evil: Rodrick does a lot of actions just to show what an evil Jerk Ass he is; he has his sidekick send four soldiers to their death which in-turn leaves the group with barely any rations. And then he goes out of his way to throw another one off a cliff for literally no reason despite knowing he's in a hostile territory and could use the protection until he seized control.
Discutible: He wanted to control the giants with the crown, and the less people who could challenge his possession of it, better. Except for his henchmen, all the others were disposable, and rescuing the princess was just the perfect excuse for going up the beanstalk.
The Smurfette Principle: Other than her mother's brief appearance early on, Isabelle is pretty much the only female character.
The Starscream: Fumm clearly doesn't care for Fallon and goes out of his way not to help him when Fallon falls into the fire moat.
Toilet Humor: While not constant, the giants do fart, belch and pick their noses, forgivable because they are portrayed as being grotesque creatures.
Your Princess Is in Another Castle: Roderick is dead, the princess is saved, the beanstalk has been chopped down, stranding the giants in their land... Shame on you if you expected the movie to end at this point.