First check of the Content advisor options in IE (you didn't tell which version, in IE8 they are in the Content tab of the Internet options) are sufficient. See
http://www.wikihow.com/Restrict-Web-Browsing-Using-Internet-Explorer for an introduction.
If not, find a Parental Control program (even if it isn't your child you want to restrict, but some other user) that suits you. I think it comes with some Internet Security Suites (like Norton, and others), but there are also stand-alone programs.
http://www.google.com/search?q=parental+control is a good starting point
I have one problem... On one computer with installed win xp sp3 I have 4 users (limited accounts). For security reasons, I need to allow 3 user accounts unlimited access to the web, and one account restricted access to the internet. That one "blocked" user may go to few web pages I would allow him to go.
does anyone here knows how to do it free of charge?
For surfing is used mozilla firefox and IE...
help, I really need to solve this issue as soon as possible.
I apologize if this thread is in wrong forum...