With examples of Flight Simulations and Racing Simulators being effective ways to train people, and with the Army having their own video game, it is not surprising that so many people are afraid of games being murder simulators. The issue of course is the necessary conversion and physical conditioning necessary to convert the video game/simulation experience into real life ability.
So, those kids who shot up schools and other kids, who claimed "video games" made them do it, would not be able to do what they did without real world training. They practiced firing real weapons first. Otherwise, the recoil would most likely have resulted in them hurting themselves as well. Just like a pilot or driver must train to resist the G-forces of actual flight and racing to not pass out or throw up.
With that in mind, what kind of games do I let my 6 year old play? Gardening games, reading games, math games, shape games, puzzle solving games, racing games, action platform games (the most violent games he plays). I also sit and play games with him, and ask him questions. He counts everything. I read to him, and make sure he reads a book every day.
I wish more parents took responsibility for their kids, and stopped trying to blame video games for the violence in schools. GTA: San Andreas has sold over 21 million copies (pdf), and we do not see 21 million school shootings since 2005. In fact according to infoplease.com, they have 19 school shootings from 2005 to 2009. The wikipedia article has 32 shootings from 2005 to 2009. So regardless of how many people have played a violent video game such as GTA, the number of school shootings is low compared to the number of sales. If there was ANY causal effect, we would see gun violence in schools up in the millions per year. Instead, we have less than 40 in 4 years. Though that number can be considered high because of the destruction of human lives, it is low compared to the number of violent video game sales.
With everyone talking about how video games can be used for learning, and how effect games can be to helping children learn, it is interesting to note how violent video games is NOT leading to healthy kids becoming deranged. Instead, we see kids that had other problems who liked playing violent video games. If it wasn't video games, they'd blame a porno, or a movie.