Make a note of the recent Windows updates then uninstall them and see how the computer behaves.
If the computer runs ok install the recent updates again but this time do it manually/one at a time and see if a certain update is causing the issue.
Next run SFC (system file checker)
Go to Start and then to Run ("Start Search" in Vista - 7
Type in: sfc /scannow
Click OK (Enter in Vista - 7)
Have Windows CD/DVD handy (not always required).
If System File Checker (sfc) finds any errors, it may ask you for the CD/DVD.
If sfc does not find any errors in Windows XP, it will simply quit, without any message.
In Vista - 7 you will receive the following message: "Windows resource protection did not find any integrity violations".
For Vista & W7 users ONLY: Navigate to C:\Windows\Logs\CBS folder. You'll see CBS.log file.
Usually, it's pretty big file, so upload it to http://www.mediafire.com/
and then post download link here.
How to use mediafire http://en.kioskea.ne...es-to-mediafire
Thanks for the additional assistance SleepyDude