I've never read any of the Marvel comics and knew nothing of the story. Didn't hinder my enjoyment of the film. Robert Downing Jr. was superb as the brilliant rich science geek playboy.
Put this on your movie list even if you only see a few movies a year in the theater. Not lame at all. Gwenyth Paltrow (Virginia "Pepper" Potts) is easy on the eyes and her character is quite competent and intelligent.