Hulk. He just gets pissed off as Superman keeps hitting him. The more pissed he gets, the stronger he gets. However, Superman could just take him to space and leave him there to suffocate. Could go either way.

I would think it would depend on where they fight and where they're allowed to fight. I think people forget just how fast and strong Superman is. All he would have to do is fly at max speed to the Sun, spend a couple minutes in it, and fly back at max speed and infinite mass punch the Hulk.