X-watch is good, so are others like Surf control and net nanny etc.
I havent used X-Watch so i wouldnt know if it has a custom blocking list or not.
If he still gets through the IE Content advisor, which is easy, as you have to remove one key from the regedit or change the ratings.pol file to ratings.old,
Anyways, if he still gets through, check the websites he vistis and add them to the HOSTS file with the lookup address as the loopback, 127.0.0.1
About Kazaa, blocking Kazaa.com etc has nothing to do with kazaa downloads,
Kazaa works on p2p protocol and opens up randon ports and connects to random ip's(In the case of downloading from someone) to download.
Kazaa has a conetnt restriction, family filter, or whatever they call it.
You can pass protect it.
It's pretty self explainatory, mess with it a little and you'll get it.
Also, if you want restrictios implied on the box he uses, you can manulay edit the registry keys for hiding of stuff you dont want his acces to.. the run button or Internet explorer etc etc.
If you dont know the keys and the way the operate(Dword values, String values, 1=enable, 0=disable etc) then i recommend Winboost.
Google for it.
Also, you can get a firewall, (Highly recommend Outpost) it has a content restriction in it aswell.
You can specify words that a website contains, which is to be blocked.
In your case, obscene words, and phrases.
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