In a straight up fight Green goblin would win due to the amount of tech he has available to him. I mean the Joker is just a man with a painted face, true he has weaponry training but verses the speed of goblins hoverboard thing, the regenritive qualities of his armored suit and the, seemingly, infinite bombs he carries with him. He would easily defeat Joker.
The Joker for sure. People seem to forget that Heath Ledger joker isn't the only joker. The Joker has some pretty high - tech stuff too, and always manages to weasel away from Batman. Joker, definitely
I don't know if your making fun of people like me or you just don't know. JOKER........DOESN'T...........WEAR.........MAKEUP. Joker is a super genious serial killer chemist slash inventor. Green Goblin is a bit like that but not as smart.
The Joker seems like a much more cunning villain to me than the Goblin. I don't know much about the comic books from either side, but that Joker seems like he could always be one step ahead of any adversary... except perhaps Batman.