Halloween films... any recommendations?

Um... it's not going to be very often that I solicit advice on movies from anyone - so have at it, this is your chance.

I need 3 scary movies suitable for a bunch of 13 year olds. I haven't scoured the local DVD store yet to check the ratings, but I'm initially leaning towards:

Poltergeist (I went to this at the time expecting a laugh & ended up chewing through my jacket...)

Halloween

Friday the 13th...

Any ideas?