Bloody hell. I've thought about this for days and still can't decide.
The first thing is to get past the fact they are both pacifists.
Second; look at their backgrounds: Jesus was a carpenter, plus he was of hardy desert folk. Buddha was the son of a warlord and most likely trained in that fashion in his youth.
Third; who can take a hit best. Jesus suffers for all mankind, and Buddha believes life is suffering.
Finally; what gnarly powers do they have? Now Jesus multiplied the fishes and loaves, and he turned water into wine, so could he take a muffin and transform it into a harpoon? But then Buddha could like, distract him with his logic and stuff. "Birth is painful, old age is painful, sickness is painful, association with unloved objects is painful, separation from loved objects is painful, the desire which one does not obtain, this is too painful - in short, the five elements of attachment to existence are painful ...and this is going to be painful too, muthafuckaaaaa!!!" And then leap on Jesus and snap his neck.
Honestly, I can't decide. Sorry.