Awesome, Dear Boy: Most actors just jumped at the opportunity of being in a Star Wars movie.
Beam Me Up, Scotty!: A minor one, but Anakin is sometimes associated with the line "This is so wizard!" or variations of the line; while the line is in the film, it's actually said to Anakin by Kitster.
Nathan Hamill (Mark Hamill's son) has an uncredited cameo role as a Naboo royal guard.
Cast the Expert: Darth Maul was played by Ray Park, who was a martial arts expert and stunt man, not an actor, although he has had a number of acting roles since then. This is one of the reasons that he had virtually no lines, and what lines he had were dubbed by Peter Serafinowicz.
Creator Backlash: Several of the film's actors regret working on the film or just plain hate it.
Jake Lloyd isn't fond of his role in the movie, thanks to having been mocked about it since childhood. He went through a phase where he destroyed all of his Star Wars memorabilia and refused to talk about it. However, an interview with a Star Wars fan site has confirmed that he's mellowed out since then (it's still a sore spot, just not as raw anymore) and contrary to popular belief, he does not hate Star Wars after all the bullying. He also criticized the prequels, feeling that part of the problem with them was that they were made for children and George Lucas didn't try to make them live up to the expectations of adult fans.
Ahmed Best liked working on the film and doesn't hate Jar Jar Binks (the character he voiced and did mo-cap reference for), but he admitted that he totally gets why people hate the character, and he has stated that he will not reprise the role in any future works.
Anthony Daniels (the actor behind Threepio) has stated that he doesn't care much for the film or the prequel trilogy in general, feeling the films were cold, bleak effects showcases.
"Ah, the prequels. I turned one on the other night... The effects are clever but pointless. The skill is there, but so what? Coldness, that’s the word. Bleakness, even.”
Peter Serafinowicz didn't care for voicing Darth Maul either. He criticized Lucas' poor direction to him, which just amounted to "Make him sound evil." and he was not happy that only three of his lines are in the movie, and that he only got a meager salary for those lines. On top of that, he was annoyed that he wasn't even invited to the film's premiere and had to pay for his own tickets and travel expenses, and he didn't think the film was very good on top of that.
Natalie Portman also regrets working on the film, saying it nearly torpedoed her acting career, and she refuses to show it or the other prequel movies to her kids.
“Star Wars had come out around the time of Seagull, and everyone thought I was a horrible actress. I was in the biggest-grossing movie of the decade, and no director wanted to work with me.”
Terence Stamp was also unhappy working on the film, describing it as a boring experience and he was miffed that he didn't actually get to work alongside Natalie Portman. This is partly the reason why he refused to reprise his role in Attack of the Clones.
Documentary footage of the making of the film shows George Lucas and crew screen a rough cut. The general reaction seems to be an uncomfortable Stunned Silence, with Lucas himself quietly noting that he "may have gone too far in a few places."
Deleted Scene: This movie, like the others, has its fair share of deleted scenes. One of the more notable ones is where Qui-Gon and Anakin start to depart from Tatooine. One of Maul's sith droids attempts to tail them, only for Qui-Gon to suddenly slice it down, and then explaining they need to hurry back to the ship. This scene explained why immediately in the next scene, they were running back to the ship when the previous scene had them walking calmly from the market.
Another notable deleted scene, taking place after the podrace, involves Anakin beating the crap out of one of the other kids because he accused Anakin of cheating. Would have foreshadowed Anakin's prone to anger. Anakin's victim? A young Greedo.
Another scene had the pod the Jedi use to get to Theed surface in the city... and then have to be quickly abandoned before it goes over a waterfall. It was most likely cut for making no sense whatsoever.
Easter Egg: Aliens from E.T.'s species make a brief, split-second appearance in the Galactic Summit scene.
For Jake Lloyd, who soon after retired from acting owing to the mockery he endured in his youth as a result of his performance. Some friends of his from high school noted that he would sometimes fly into a psychotic rage when asked about it.
Also for Terrence Stamp, who reportedly disliked working on the film, which led him not to reprise his role in Attack of the Clones.
The heroes visiting an underwater city to parlay with its ruler was originally a big plot point in Lucas' first draft for the original film, The Adventures of Starkiller: The Star Wars.
The idea of Anakin bypassing a blockade by using the Force to come out of hyperspace at the very last moment before crashing into Naboo was revisited in The Force Awakens. While Han Solo doesn't use the Force, feats such as this one make some fans assume that he does.
Sequel Gap: 16 years between this and Jedi's release. The lead actress was two the year the last one came out.
Spoiled by the Merchandise: The soundtrack to Star Wars Episode I The Phantom Menace was released before the movie itself came out. Anybody who picked it up got treated to tracks called "Qui-Gon's Noble End" and "The High Council Meeting and Qui-Gon's Funeral." Oops.
Both Ewan McGregor and Natalie Portman were well respected actors but were in either small roles or independent films. This movie made them big names. Ray Park also fits in, as his presence in the final battle was one of the most memorable parts of the movie.
On the other hand, it was a Star-Derailing Role for Jake Lloyd. He was never a star, but he had a respectable career as a child actor before this film. He did one movie after it and then quit acting. He said in a recent interview though that he's pursuing a career in film editing, so he isn't totally gone from the movie-making scene. One can only hope he has/had access to Wil Wheaton as a mentor.
In the earliest drafts, there was no Qui-Gon, Obi-Wan had the lead role, and Jar Jar had larger and more important role than being comic relief. Also when the crew returned to Naboo, the Trade Federation blockade was still supposed to be in place, and Anakin was going to land the Queen's ship by using his Force-intuition to divine the last possible moment to bring the ship out of lightspeed, before they crashed into the planet surface.
After Lucas decided to show the old Master-Padawan setup of the Jedi properly, he considered making Qui-Gon the Padawan.
George Lucas originally wanted Tupac Shakur to play Mace Windu, but he was killed before filming even began.