Well i'm intrigued now. I assume you downloaded and ran the Kaspersky scanner. It should have found all kinds of rubbish on your 'puter if you have been running Norton. Again i'll assume you killed all of the rubbish found. Reboot and you should have been golden. Did you run Spybot and ad-aware? Perhaps found a few more nasties but i really can't see why this would cause such instability.

Did you uninstall Nortons before installing Kaspersky? Wouldn't be a major problem, but they might clash. Get rid of Norton either way.

Sometimes Kaspersky can be a little tricky if you're using an older version. You have the 6.0 version?

Other than that you could run the chkdsk command. It might not be a bad idea to do it anyway, particuraly if you have removed a lot of rubbish with the anti-virus. It's an inbuilt Windows repair command (XP).

Start menu
Run
type: chkdsk /f
enter

A small DOS window should open. It will tell you that it cannot perform the test at the moment as the drive is in use. It will ask you if you would like to run the test the next time the system is restarted? Type Y and reboot.

Other than that i'm not sure what the hell is going on.

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