The original "Night of the Living Dead" creep'd me out. Grainy, black and white, cheezy acting and those manical zombies. Saw it in the drive-in when it was first released. I was riveted. Didn't even bother to make-out with my girlfriend.
The Exorcist is the other topper. The anticipation of "what's next" made it scary. Jaws, as an ocean swimmer, I felt every bite.
Forgot about Romero's Night of the Living Dead. You're right on that one. Yeah, Jaws kept me out of even freshwater for a while after I saw it!