As you may know, Scary Movie was originally the working title for Scream. In spite of what anyone might say, I thought Scream was a pretty darn good flick. I liked it a lot. It was original, smart, funny, and even scary. Scream was, at its most basic, a parody of teen slasher movies.
Scary Movie was unoriginal, unfunny, and stupid. The only scary part was that people actually liked it. It attempts to be a parody of horror movies, but all it does is tie together the most popular parts of films with stupid dialogue and gay jokes. The "Wazzaap" scene wasn't even close to being funny. I could see the same thing on TV (except for the guy in the mask), and I'd still not laugh.
Scary Movie was neither funny nor scary. I'd say it should have been called Movie, but that would be misleading, since a movie necessitates something resembling a script.