Growing up there were three movies that scared the crap out of me while I was in the back seat of my parents car at a drive-in theater:
The Crawling Eye (1958)(Those monsters took up residence in my closet)
The House on Haunted Hill (the 1959 original Vincent Price version)(Had nightmares for years)
The Crawling Hand (1963)(Expected to see that hand in my bedroom for about a decade after watching that movie)
Senior year in high school:
The Exorcist (1973)(Didn't earn any macho-points with my girlfriend on that date)
Sitting unsuspecting in a $1-night theater in Kingsville, TX not having any friggin' idea what's coming:
Halloween (1978)(I was expecting a comedy for some reason)
Alien (1979) (I just wanted to see a cool Sci-Fi movie. I can still remember jumping through the roof when the full-grown alien suddenly appears out of the darkness in a crawl space)
The year I got married and learned my new wife HATES scary movies:
The Shining (1980)(My wife still hates Jack Nicholson because of this movie. I had to drag her to "The Bucket List" because he was in it)