REDRUM!
As odd as it may seem, I've never seen The Shining in a theater. In fact, I don't even remember hearing about it until I happened to stumble upon it while—unable to sleep for some reason—cable surfing at 2 am back in '81 (or maybe '82).
It scared the fuck out of me.
And while I know it's not faithful to King's source material, I still prefer it over all subsequent attempts to bring The Shining to the big screen.