God, this was a tough choice. I liked all three 'big names', Hulk/Banner was good but didn't have nearly enough screen time, and Black Widow was quite more interesting than I expected... but when It comes down to it, I had to go with Iron Man. Robert Downey Jr. has Stark down to a science. A beautiful, narcissistic science... second choice would have to be Thor.
Devious Comments
I went with Hulk for the comical beat-down he did in the last fight.