Net Nanny I guess but remember Warez anything can be broke if you are deturmined enough you should know that.
Noton Internet Security 2005 also has some built in adresses to block and you can choose them from the form of a list or check boxes and you can also manually add in the blocked adresses.
Depends upon the ages of the "children". I had Net Nanny when was son was much younger. He and his friends at school developed a hack program that they used to disable the protocols from the DOS prompt in Safe Mode. They are not infallable. If my wife installed Net Nanny on my computer without my permission I would be instantly reformating and Admin blocking her from my puter........he must have agreed so he could overcome his Ebay or porn addiction.