Halloween H20: 20 Years Later
The riff of the original Halloween was hilarious, even though the movie itself has some slow parts. Although I'd love to see all of the Halloweens done, I feel this one has the greatest potential of being Rifftrax gold. Halloween 3: Season of the Witch would also be hilarious in its own right; totally ridiculous movie.
With Jamie Lee Curtis returning, Josh Hartnett (he's such an edgy teenager in this movie, I think it's his first film role), LL Cool J (plays a security guard who aspires to be an exotic romance novelist and manages to pull another Deep Blue Sea on us), a very minor appearance by Joseph Gordon Levitt, and Michael Myers' amazing speed walking ability, I have a feeling this would end up as one of my favorites.