I loved Godzilla and any other giant monster movie I could watch as a kid. I was also big on the Universal Classics as a kid. Frankenstein was a favorite, but I've always loved Invisible Man. Still love that one, and I've got the Legacy Collection.
The first movie to really scare me was part of The Exorcist that I was when I was about 4 years old. I'm not exactly sure what part, I'd like to say the stairs, but it scared the hell out of me.
From then on trying to find a movie that scared me became a bit of a fascination. I really enjoy finding something that truly and honestly scares me. The only recent movie I've seen that scared me was The Orphanage. It was so atmospheric that walking through a house similar to that one scared me.
Another one that got to me was the original Night of the Living Dead. I watched it at 2 am with a friend. This friend lives in an old farm house. I had to go to the cellar to get more pop after it was over. Walking down the stairs, I noticed a table with a trowel on it. All I could think about was the lamp swinging. That did it for me... That basement still creeps me out.