I heard the original Halloween was praised by Ebert as a departure from the cliches of the genre.Casual Shinji said:You're not talking about horror movies, you're talking about "Slashers".
And all Slashers suck except for The original Texas Chainsaw Massacre.
OT: I don't watch a lot of horror films, but the ones I've seen didn't use a lot of sex/ nudity.
Well, maybe Alien(s) had some symbolism, but that was about it.