Ringu! (Japanese version of The Ring...j/k do not watch that with him. I cried watching that movie)
I watched that first American one during the only time of my life where I was seeking out the scariest movies I could find. Normally I'm a ginormous wimp about them.
I did find it scary, but there was this odd thing where the cut of the film they were showing often showed the boom mic in the scariest of scenes. I remember watching Amber Tamblyn in a super scary scene with this mic hanging over her head and some rigging also showing thinking, "Ah. So this is why the actors aren't scared shitless when filming..."
That all said, that movie minus the filming apparatus would scare the piss out of me right now. Just THINKING about the premise makes me never want to play a VHS tape again.