The thing about his movie is that he was like, almost okay. Iron Man I was about him learning that selling weapons = bad. He could have continued his moral development.
Instead, we got him fighting Captain America over a very stupid implementation of 'oversight' (coming from the guy who refuses to let gov. oversee his iron man development), being creepy to some random boy he just met (actually twice - first Peter and then some kid I don't remember; in a better set of movies I don't think Peter would be very thrilled to realize Iron Man was advocating for Peter to get outed in a national registry), and having a snit fit about how he doesn't want to help Unsnap people who died because he personally is OK with his future with his daughter who may or may not be a robot he built to mime having humanity.
What makes him really insufferable for me is his fans who think Captain America is EVIL for daring to snub poor Tony, and that Tony should go date Loki (no I'm not kidding; while I am happy with Loki being queer, I really can't see the Marvel Universe Tony being a good date for, well, anyone ever, nor Loki being a good date until he works out his genocidal tendency issues at which point he threatens to become alas a much less interesting character).