A Nightmare on Elm Street - the first of the series. I can't imagine how many people were probably afraid to fall asleep after watching this movie! Bonus points for getting to see a young Johnny Depp in it!
The Goonies One of my all-time favorite movies as a kid. I remember watching it on the back porch of my great-uncle's house on the Ohio River with my cousins one summer. My whole family loves it and we have a recurring joke about "that kid from Goonies.