I agree with the unregistered poster just above.
A logical instinct for a parent is to want to create a hermetic, disinfected cocoon for their children where everything they see and hear is all sweetness and roses. Perhaps if you brought them up in the wilderness in a house with no electricity, 'phone lines, cellphone coverage or neighbours it might still be possible, but somehow I doubt that many users of this forum live in those conditions.
I've read many articles and posts on the filtering internet/P2P for children issue and I think , like many things, it needs to be placed in context: Imagine that you were able to filter all illegal/adult content from the internet and P2P software (which as others have said is very difficult to do). The child finishes downloading a non-copyrighted song from his favourite file-sharing program (
) and trots off to watch TV where he sees an ultra-violent, stroboscopic Japanese manga cartoon followed by the news with various images of Israeli tanks and American B52s bombing anyone that looks vaguely Arab. He then goes for a walk in the park with mummy where he sees a drunk bloke swearing at his girlfriend and a teenager sniffing glue. When they stop to buy the newspaper, he sees a row of life-sized, naked Barbies all siliconized and retouched in Photoshop on the top shelf. On the way home they pass a man picking up a prostitute. He then returns to his room for another session surfing the squeaky-clean kiddy-net.
You might be able to filter the internet, but you can't filter the world. Part of a parent's responsibility is to monitor and explain. Simply banning and censoring is not going to do the trick - in fact it will probably be counter-productive and arouse the child's curiosity more.