Improved by the Re-Cut: The DVD Extended Edition, which includes all deleted scenes (such as Ben and Alicia's romance) is a much better watch than the theatrical release of the first film.
Narm: The film pulls the Wilhelm Scream two times during the final battle. Once when Doctor Doom gets blasted back into the bus, and another time when Doom starts to try to electrocute the watching citizens. One Wilhelm Scream is already usually quite immersion breaking, but the fact the film does it twice almost back-to-back is just insane.
Never Live It Down: Doctor Doom's most memorable quote is "I don't want to understand it!" Naturally, fans think that Doctor Doom refuses to understand anything.
Stan Lee as Willie Lumpkin for playing a character he created.
Hugh Jackman's facial cameo in the extended cut.
Padding: One major criticism of the film is that it focused more on humor than action throughout the middle Act of the film. The result is the Fantastic Four basically just sitting around waiting for Reed to finish his machine that will return them to normal, and only briefly switching over to Dr. Doom from time to time to show him performing evil deeds.
The dark haired little girl who Ben says "Don't do drugs" to? Well, that's the young Lily from Once Upon a Time, or else Christie Macauley from Defiance.
Signature Song: "Noots" for the scene where Johnny Storm activates his powers.
Take That, Scrappy!: Those who didn't like the cartoon starring H.E.R.B.I.E. are glad he is a dismantled machine in the extended cut.
They Copied It, So It Sucks!: A common criticism of the movie is that its spends too much time trying to copy Sam Raimi's Spider-Man Trilogy whether it be adding a campy humorous tone, taking a grounded approach and not exploring the cosmic and subterranean parts of the early FF adventures, or even changing Doctor Doom to an evil CEO like Norman Osborn.
Unexpected Character: In the extended cut, nobody expected Reed Richards' face to change into Wolverine.
Visual Effects of Awesome: The "Thing" costume Michael Chiklis wears is a pretty good comic-accurate costume made with practical effects (as requested by Chiklis), and was only CGI for things that were necessary (like when he's being thrown through the air), His actor's dedication to making the prosthetic teeth work (see the Trivia tab) make him one of the best-realized comic book characters put to film.