These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Crosses the Line Twice: The scenes where Tony kept smacking into things while testing his suit was funny in all the wrong ways. "10% thrust." Splat!
First Installment Wins: Many viewers find the first Iron Man to be the best film in the Marvel Cinematic Universe, or of the Iron Man films at the very least, and it's hard to overcome the perception that Tony Stark is the overall protagonist of the entire MCU by virtue of being the first hero to be introduced.
Either this or Hilarious in Hindsight depending on the viewer, but Iron Man mistaking Stan Lee for Hugh Hefner (since he was wearing a similar getup as well as being coddled by blondes) is especially ironic when fans remember that Stan Lee is responsible for the creation of Stripperella.
The formal event in the middle of the first film takes place at the Disney Concert Hall (guess who owns Marvel now?). Also, the fighters pursuing Tony go by "Whiplash" One and Two (the Walt Disney Concert hall has nothing to do with the Disney company and was endowed by a private foundation in Walt's name, but it's still pretty funny).
Downey is also seen at the Disney Hall in The Soloist with Jamie Foxx a year later.
It Was His Sled: "The truth is... I am Iron Man." Unprecedented in any superhero movie before, its effect is lessened now that none of the supers of the Marvel Cinematic Universe even have a secret identity.
The fact that Nick Fury arrives in The Stinger to recruit Iron Man for the Avengers is pretty well known now. Kinda $3.8 billion dollars well known.
Also, the fact that Obadiah Stane is the main antagonist. Even promos that came out around the time of the film's release didn't hide it much. Case in point
TONY STARK WAS ABLE TO BUILD THIS IN A CAVE! WITH A BOX OF SCRAPS!!!
I am Iron Man!
Moral Event Horizon: Stane pushing the board to file the injunction against Tony. Weirdly, this is completely innocuous in the world of business (not exactly nice, but sometimes it's a very necessary move). However, the reason it is the Moral Event Horizon is because we learn that he did right after Tony confronts him about dealing on the black market.