[Grimnir]

Batman Begins and Dark Knight would edge it for simple reason that I wasnt a fan of Iron Man 2 (similar to how I loved Transformers but didnt like Transformers 2)

I loved Iron Man and put it on par with the 2 Batman films for enjoyment

I would rate them

The Dark knight 9/10
Iron Man 8.5/10
Batman Begins 8/10
Iron Man 2 6/10