I'm not sure anymore. (And why do we need favorites of everything?)
I read about Superman being a one dimensional character, and now I see that, although the 80's Superman movies had a nice, but dorky vibe.
A lot, like Batman and Spiderman, are kind of emo-ish now.
I'd go with the modern Batman though, Bale-Nolan version. Mainly because I just watched a documentary about it. Some of the technology Batman uses isn't that far fetched. It's a super hero but it represents technology that can be developed and used, developed by real people, used by everyone.
Which is kind of ditto for Ironman, but there's no power source like that. That's a step farther out there.