Run this free online virus scanner!
http://housecall.antivirus.com/housecall/start_frame.asp
Another good program to use is Ewido, get i here:
http://www.ewido.net/en/download/
And of course Adaware:
http://www.pcworld.com/downloads/file/fid,7423-order,1-page,1-c,alldownloads/description.html
Also if you wish to format:
1. Insert the Windows XP CD-ROM into your CD-ROM drive, Restart the computer.
2. When the message comes up "Booting from CD, Press any key to continue" do so.
3. At the Welcome to Setup page, press ENTER to continue.
4. Press F8 to accept the Windows XP Licensing Agreement.
5. If an existing Windows XP installation is detected, you will be prompted to repair it. At this point hit the ESC key (do not repair).
6. Now you should be given a list of partitions, select the one where Windows is installed to. (Usually drive "C").
Press ENTER!
Follow the instructions step-by-step (Everything will be explained to you).
And printing this out before formatting might be helpful as well!
But if your going to take your computer to get it "Repaired" You may as well have a shot at a format.
And when you get the choice's on different ways to format choose the one that says:
Format the drive with the NTFS File system (Quick).
From then on in, it should be easy!
Remember, When you format EVERYTHING will be deleted, allowing you to start from scratch. So I suspect you still have all your CD's with drivers on them, That came with your computer?
Anyhow, If you need any questions answered give us a buzz