Hmm,hard one,Shinkenger VS Go-Onger was pretty funny. The Gosei one had it's humourous moments.
I can't think of a real laugh-out-loud film. Bill and Ted and Wayne's World are a bit like that. I liked the start of Napoleon Dynamite and the end of Zoolander when I watched them in school!
I think Scary Movie 3 was pretty funny. I don't like the first one. Oh and Shaun of the Dead.