Was generally quite unflappable as a child, and saw a lot of things a lot earlier than I probably should have done. Most of it failed to bother me.
What did? (don't laugh too hard) - Orca, Killer Whale, with Richard Harris. There was something about the idea of a whale with a grudge that went against all my childhood instincts and freaked me out.
Also (more conventionally) The Devil Rides Out and Witchfinder General - proper scary. Again, I may have been younger than I ought to have been while watching them for the first time. The Wicker Man is of a similar ilk - but it always seemed to me that it ought to have been more scary than it actually was.
Oh, and I was also terrified by/had nightmares about Sam the Bald Eagle from The Muppet Show.
[fetches coat/leaves]