Just saw the above list a few minutes ago. Some of them I didn't see (mabye they were solely American...or I just missed out?). So the Dark Crystal (my fear of birds began with Skeksies) and Land Before Time are definately on my list. But I'd add these ones as well:
The Last Unicorn made me so sad. I mean you turn her into a girl, and then the guy falls for her, but she's confused and can't remember being a unicorn...OMG make it stop. And that mama vulture creature thing freaked me the hell out.
Easter Fever. Not scarring because it's scarey but because it was confusing. Easter Bunny is a perv. And that whole Chef Piggy Lady egg scene was a big dose of WTF?! I still can't beleive that this was made for children. Weird and full of innuendos.
The Devil and Daniel Mouse. Essentially Faust for kiddies. More innuendo and a seriously freakish devil character who was quite unsettling and difficult to process for my child brain. So bleak and dark.
ET. Never saw him. Started crying at the first scene when the closet door begins to open. Freaked me the hell out. Still haven't seen that movie to this day.
How about you guys? Anything really unsettling or frightening that you watched as a child? Or something that you loved as kid but aren't quite sure, as an adult, that it was appropriate for children at all?