IT was pretty bad, because I saw it so young. Weirdly, I'm not afraid of clowns or anything, so no lasting trauma.

Outside of that "The Ring" really fucked with me in a big way, like in a slept with the lights on for a couple nights kind of way, and was generally kinda anxious around static-y tv's for awhile. It didn't help that I had a huge sony trinitron TV in my room that wasn't hooked up to cable (mostly used for nintendo) so when it came on it was basically just like the movie, with the loud static and snowstorm pattern.

I eventually got over that too.

I was really sad when Old Yeller died in the movie of the same name.  Wouldn't be surprised if I actually cried.

LLAP,
Swim

Stayed up late watching it and then just before bed I thought I saw it coming down the street.  Was awake all night waiting for it to come down the hall and absorb me.  (shivers!)

-DkG

I watched "Deep Throat" and was worried that I was going to someday have to stick my dick in a mouth full of teeth in order to make a girl cum.  I would wake up in the night from a scary dream about a girl severing my penis with her teeth.  Here I am 45 years later and the only blood that has been drawn were from two girls with braces.  

2nd one was the original "Alien", which was the most serious Industrial Weapons-grade Monster movie, when the exomorph was the surprise guest at the dinner table.  

Never wanted to go in the ocean after watching that movie.

...door and when she opens the door, she'll look like...

I'm not really sure why.  I think the fact that it was a true story was hard for me as a young kid.

Star Wars was my 1st movie theater experience.  Age 5.  Opening scene when Darth Vader walks through the cloud of smoke in the cut door opening freaked me out.  That's what the dark side of Star Wars has lost over the years.  Rest of the movie I loved and was excited.  But for weeks after I had nightmares about that Darth Vader scene

Second was Time Bandits when the wall in Kevin's bedroom pulls back and the time hole appears.  Never looked at my own closet door the same after that.

Event Horizon

A cock that big and a mustache was too much to try to live up to.  
It took me a long time to get over having a statistically average appendage.

Agree "Exorcist" of course, but Zuni Fetish Doll from "Trilogy of Terror" with Karen Black- that seriously fucked me up!

Summer of 42

I have been relentlessly horny to make out with women ever since!

I don't know what my older siblings were thinking taking a kid to see that movie. Violent nightmares ensued.  Nice tits on Michael's Sicilian bride though.