Personally, I find many of the the video games and what is called "entertainment" on TV and in the movies, to be abhorrent. As for me, my wife, my children? We stay away from it.
However, I would not to presume to make that choice for anyone else.
It's more than just one single influence. These things may twist a troubled mind? They could, rarely, twist a "healthy mind?
You can't legislate, ban, or stigmatize your way to safety.
I've heard the argument, on the the forums, that..."kids have been playing war, or cops and robbers, or cowboys and indians for generations. Video games are just an extension of this..."
Growing up, we played "War" in the woods. We also had guns (not to play "War" with). We were taught to use them, safely. We understood the responsibility that they required.
What's more, we understood death. We raised animals, to eat. We named them, we cared for them, we killed them, we butchered them. We hunted, too. Not for sport, rather, for food.
We learned that actual death and killing is not a game.
Now my kids? They shoot real guns, they are taught an honest and balanced truth...about life, death, responsibility and safety. Guns are a fact of life, like the kitchen knives. Neither good nor bad. Possessing no taboo fascination with a hint of perversion. (My guns, except for what's being carried on my person, are locked up. None the less.) My children are surrounded by children who are immersed in the most violent and depraved movies and First Person Shooter games (FPS games). I hear constantly, from my kids, about it. About how their schoolmates are consumed with the images and fantasies about doing it.
But, it's not the movies, or stupid TV shows, or FPS games. Sure the pervasiveness of the particular culture we find ourselves in plays a factor.
The blame? That goes to the parents. Parents need to raise their kids, not the school system, or government, or conflicting laws. Parents need to actually take the time to teach, BY EXAMPLE.
It burns me up, the parents that tell their kids, "oh guns are bad!" Then turn around and let them be inculcated by extremely violent games and movies. This gives a warped view of guns and their place. This warping doesn't make monsters, it fuels them. It can.make degenerates, though. As more generations of degenerates make more degenerates. It leaves the ratio of responsible to reprehensible, all out of proportion.
You can't legislate good parenting. It's a cultural thing.
You can't ban your way to good parenting either.
These forms of "entrainment" are already "rated" according to appropriate age. Parents need to be involved in there selection.
While I'd debate their value. I wouldn't make that choice for you.