If you system is running slow or giving error messages on startup you probably just have to many programs starting up behind Windows. For info on how to clear out your startup group, and disable the unneeded things that are slowly your system down. Goto:
http://sourceport.gotdns.com/computers.php
Click the link for "What's Starting up with your system?" and follow the instructions. Also there is some information about using Adaware and Spybot to remove spyware. Those are great articles to help remove spyware. Spyware usually gives popups and tried to get your information so that advertizers can spam email you etc...
You can also go into Control Panel and uninstall old or unneeded programs. From your system that will help to free up some Hard drive space.
They also have a Tech Forum that you can sign up for and Post a question or Answer a question someone else has.
http://sourceport.gotdns.com/forum/