1. Yes, the likes of Mortal Kombat, Doom II, even played a fairly uncommon game by the name of "Harvester" on the PC at the age of five. It was one of those FMV type games, one 'boss' involved you aiming for his head and shooting, once defeated, you'd see him grasping his head and screaming in pain, followed by a nice explosion, consisting of brain fluid and various bits of body meat. Nice. Too bad the gameplay was about as fun as shoving blades under your tounge.
2. I think have video games to thank for my total lack of 'gross out' factor. I've sat through a VCD of "Faces of Death" and ended up smirking at some of the more hilarious deaths, my friends got to the point where they couldn't look on anymore..
3. Tough one. I very much doubt video games corrupt children, sure, some pre-teen might have an unhealthy amount of fun blowing the heads of old woman in GTAIII, but it's an escape. A stress reliever. Without these violent games, we'd most likely see more school shootings and so on. Society is one big kick in the face these days, kids go through more and more stress, even at tender ages. They need to escape once and a while..