Download Firefox and use this browser instead of IE.
If the pc still boots out of a website, you should run your antivirus, and get the free copy of superantispyware and run it as well. There are many ways for infections to get into xp but microsoft are not doing enough to close these faults, so you have to be up to date with all your software, antivirus and spyware scanners to avoid infection.
Also download Cnet Tracker, it is free from cnet download.com, and it will keep all software up to date.
sam, August 2010