A helpfull website I believe I only read about a paragraph skipping through looks helpfull to me.
http://www.kellys-korner-xp.com/win_xp_mydocs.htm
Also to help me out a bit have you installed any recent programs Antivirus Programs, games, Drivers, Hardware, basically Anything.
Anyways I imagine you have been on the internet numerous times so download Spybot - Search & Destroy
it’s a Spyware/Adware remover Gets rid of those annoying Search web pages for ya they caouse alot of problems.
Now have you downloaded SP2 if not do so now if you did contact Microsoft and tell them about your problem.
lol one last thing lol if you dont got Norton anti virus the next best free Anti virus is http://www.grisoft.com its very good you will have to lok for it in that website but it’s worth the look.