Is there a free Microsoft weebsite that sees if your pc and Xp are running ok?

Answer 1

You computer should have a health check. I know hp does, because I have an hp computer.

If your not getting any error or blue screens, then I would assume xp windows is running fine. If the computer is running slow then it's likely due to infections such as spyware and virus's. If you feel you need further help go to this website.
http://www.cybertechhelp.com/forums/

Answer 2

http://update.microsoft.com/ , you can use that to see if your computer is updated or not.

If you want to see how your computer is doing, you must do a diagnostics. To do a diagnostics, you must hold F12 while the system first starts up, then select Diagnostics with your arrow keys. I recommend a Extended Test.