Block WebSites in Windows XP:
1. Browse to C:\WINDOWS\system32\drivers\etc
2. Find the file named "HOSTS" .
3. Open it with Notepad.
4. Add 127.0.0.2 www.sitenameyouwantblocked.com , below 127.0.0.1 localhost line and that site will no longer be accessible.
well, if you can block a website, is there a way to unblock websites when they are blocked by a webfilter without using a proxy site?