Yes, The Exorcist is a classic. Also, Rosemary's Baby and The Invasion of the Body Snatchers are both very creepy and tense.
It's the remake of Body Snatchers in 1977, with Donald Sutherland, that's excellent.

I'm not much into grotesque limbs-lopped-off type of horror. I tried watching one of the "Saw" films and had to turn it off.

Cheers,
Alan

Alan Lofft,
Axiom Resident Expert (Retired)