I forgot about The Omen. Yes another good movie!

I too like "The Thing" (newer version is great).
As a kid, I remember watching Dr Jekyl & Mr. Hyde (Spencer Tracy, I think). I was so scared when I went to bed that I didn't dare take my glasses off (taking the chance of hopping out of bed.)

Fun "horror/scary" movie: An American Werewolf In London.
TIS