I would like the parents to be aware of the games that you allow your children to play, because the games can impact their minds, and can make them addicted to them before you realize. Often parents can not spend time with their children to accompany in the computer games nor they are aware of what the games are about. I think as responsible parents you should invest some time to learn what your children are playing, and how it may or may not impact them.
The same question was faced by me, as a non gaming person myself, I though computer games to be a time wasting activity and was never much interested in.
I had to share my computer with my 5 year old nephew to let him play computer games online and offline, who within a span of an year became proficient in computer games, that I had to concede my inability in helping to get around a particular game he was playing. Moreover when he seemed knowledgeable in games that had theft, robbery and violence in the gameplay, I became a little concerned.
As a society we allow and do not allow a certain things. For example we do not go and steal someones vehicles or crash them, but how come children are exposed to such ideas in computer games?
Let me put it this way. In course of talking to our children do we ever mention stealing, crashing, shooting and so on. We do not talk about them because we do not do such things nor do we think about them. So something that we don't do, nor we intend to ourselves nor allow our children to do them, then how come we allow children to engage in simulations of such things.
I feel upto a certain age children should be kept away from even the ideas of those things which would put them in harms way. That is where I decided to look at the games that I had installed on my computer and online games that I was allowing my nephew to play.
I would make a list of the games that I came across, and put them in perspective so that you can make an informed judgement whether to let your children play them or not.