DD 4.5, has only just started using the PC for entertainment (she goes to the CBeebies website, and I've been to KneeBouncer.com also in the past with her and DS).
I have to say, it does concern me that DD will be proficient in circumventing security settings when she's a bit older. Ditto DS who's 2 years younger but catching up fast.
DH works in IT, and I can see a natural interest being taken in what he does already by the DC's. DH also plays some of the pretty gorey games. He's not so vigilant about what he plays when DD is around, although that doesnt happen often. He'll also watch some films when they are around - they may be 12 cert - but IMO they are still too young.
I've never been keen on the gorey-type games personally, or like Grand Theft Auto, where the players get extra points for running down prostitutes
I dont know what I'm going to do when DD and DS hit double figures/teens. I feel that the theme of some games penetrates the minds of children more than some parents realise. I am putting that forward on the behaviour I see from some of the children in DD's class - who clearly have older siblings and watch the games that they play.
I dont know much about child psychology, but my concerns centre around what age a child is when they become aware that what they see on a tv or computer screen is not real life, and that they cant/shouldnt act out the things they see in real life.
My other concern is that other parents wont be particularly vigilant, and as a result, my children end up exposed to things at school/outside of school that I wouldnt allow them at home, or, worse still, exposed to adverse behaviour as a result of inappropriate 'games'/viewing. I dont know how valid this particular concern is though.