When you're a child, any movie can become a horror movie. Take George of the Jungle (1997), a slapstick adventure movie in which Brendan Frasier plays a guy raised in the jungle. It was wholly innocuous. And yet, whenever the film's opening drumbeats would play, 5-year-old me would hide behind the refrigerator, trembling (true story).
Most kids' movies aren't meant to torment their appropriate audiences (although some chaotic neutral movies definitely are, like A Nightmare Before Christmas and The Witches). But they're scary — and scary they remain, throughout adulthood.
Frankly, we're still haunted by E.T's croaking voice, and the very idea of talking dolls (yes, you, Toy Story). These are the movies that messed us up as kids.