Mine is the original Texas Chainsaw Massacre
Growing up in the 80s meant that pretty much any kids movie was going to be traumatizing. Gremlins: horrifying. Neverending Story: emotional damage. The Land Before Time: can’t think of dinosaurs without tearing up. It’s like the whole movie industry was explicitly devoted to fucking us up.
You also have the Dark Crystal, Water Ship Down, The Last Unicorn, Watcher in the Woods (which was a Disney movie!) and the Secret of NIMH. Seriously, kids movies in the eighties were horrifying.
For some reason, I have always found The Brave Little Toaster deeply unsettling, but I can’t really explain why.
Bonus round suggestion: was there a book you read when you were too young?
Mine was Pillars of the Earth. I was, like… 5? I think?