I won't watch anything with gore in it. House and ER I tolerated because well in those shows it happened and I'd just avert my eyes if I saw that it was coming(going into surgery, etc).
But I hate scary movies with gore in them. Blood rules, blood is great, but I don't want to see some guy's brain or intestines.
Funnily enough I can read gore(and write some of the goriest scenes ever in fanfiction), but I can't stand to see it. In school when they would show those nasty films about the inside of the body, I had to get a note to excuse me because I couldn't eat after watching those(every time I had a class with those it was RIGHT BEFORE LUNCH PERIOD! TORTURE!

) and I actually lost weight. The vision of nastiness would stick in my head and I had a stupid fear that it would appear in my food while I was eating it, especially if the food looked like or had the same texture as guts. I still have that fear, so I always eat all my snacks BEFORE sitting down to watch House.