Most of mine have been mentioned, but I’ll add:
The animated Lion, the Witch, and the Wardrobe, when they shaved Aslan and tied him to the table to be sacrificed. Every year they’d show it right around the same time they showed Wizard of Oz, and every year that was exactly the point I made it to before running from the room. I didn’t see the whole movie until I was in college.
That’s the movie I was going to mention; the scenes with the devil towards the end freaked me out. Also Sparepartski the monster from Romie-0 and Julie-8 was pretty scary at the end.
Could you please give me the link on youtube maybe? I need it for my blog.
Hell, I was done at the danged tornado!
Superman III, to my recollection, was supposed to be family friendly, but the scene where one of the bad guys is forcibly changed into a robot (or something) scared the living bejeezus out of me. Nightmares for years afterward.
I looked up the scene on youtube, thinking it would be funny to discover how non-intense and hokey it really was.
Nope. Terrifying.
Oh, a bit younger too. All of my late-70s born 2nd-3rd grade schoolmates were traumatized by Darby O’Gill when they showed it to us one rainy day.
Arguably not a kid’s film, but I always had to leave the room at Judge Doom’s reveal in Who Framed Roger Rabbit.
That voice freaked my shit out.
ETA - Here’s the full scene on youtube
Dispatch war rocket Ajax, to bring back his body!
When the boy is attacked by the bull in “Song of the South.”
In Toy Story, the scene where Sid’s mistreated toys made of mismatched parts come out from under the bed.
Yeah, I shivered a little at that, and I was in my thirties at the time.
An earlier similar thread: Scariest scenes in a kids' movie? - Cafe Society - Straight Dope Message Board
Indeed, check out The Witches for a particularly creepy performance from Anjelica Huston.