Either version of the second movie is a step down from the first. The first Superman movie is still one of the best superhero/comic-book movies ever. Iron Man is kind of edging it into seocnd place in my head. But it took thirty years for another movie to come along and do that for me.
I don't know about that. The first two thirds of the film is really good, but I've always felt the rest of it just sort of dwindles off.
The second film is far more focused, thanks mostly to the presence of actual villains.