Goldeneye - the squeezing scene
Anaconda - regurgitated people
Congo - when they throw his brain
Mercury Rising - “Mother, Simon is home”
Peewee Herman - Large Marge
The truly harrowing experience I had as a kid was the Alien Encounter ride at Disney Orlando. I was 8 and it was a field trip so the peer pressure was high. Nightmares for weeks after that. I still remember it breathing on me in the pitch dark.
You never know. Someone could make a time travel movie with it one day and then collectors will pay an arm and a leg for the left door.