Hulk in supes body would lose. He wouldnt be as versed as superman is with his powers and he wouldnt have any kind of way of taking supes in hulks body down. Supes would split him in half.
So Clark would use the strength and durability because that's sort of automatic.
But the Hulk would also use those and would likely realize he suddenly is way, way, way, waaaaaaaaay faster than he ever dreamed of being before. Even not knowing about the flight and the heat vision and stuff, the Hulk in Superman's body stomps Superman in the Hulk's body.