My youngest son was 3 or 4 when the family went to see 'To Fly' on the IMAX screen at the Cosmosphere. At the beginning of the film it is a sky shot and all of a sudden a steam engine busts into the scene with the accompanying noise. In the 360 degree theatre it looked like it was coming to your lap. I was holding my son and it scared the living shit out of him. I had to take him out of the theatre.

A couple year later I took him to see Red Dawn, about 15 minutes in I realized it probably wasn't suitable for a kid his age.

He didn't seem any the worse for it though, he's coming up for parole again next year. (JK LOL).

Rosemary's Baby was one that freaked me out.