(yeah I'm new bear with me and my comic noviceness
) well personally I think hellboy would win, yeah at first hulk would seem like an obvious choice but then he runs out of energy and becomes bruce banner again, while hellboy stays hellboy no matter what, plus hellboy has that stone arm, is fireproof, has a tail and I think is semi bullet proof at least, all hulk does is smash stuff and again, his form is temporary
although this is a worst case senario, more likely then not they become friends or something, the might get along you never know