The "Your Mom" one is probably always going to be my favorite. Favorite villain in the game. I really don't find Lavos to be a villain so much as an antagonist; it's causing the problems, but it's 'cos it's hungry. Zeal was the one who went nuts and started poking it with a large, pointy, metaphorical stick.
Otherwise, I'd pick one that had Lavos in it. You should totally make one.