Can you run a command prompt as an administrator and enter chkdsk /f to see what that reports.
You will be prompted to enter y for it to run on the next restart, then enter shutdown /r /t 00 to effect an immediate reboot and wait for it to run.
If you watch it until it completes, you should be able to catch what it reports - especially if it reports any KBs in bad sectors.
However, if you don't, go Start - type eventvwr and press enter.
Ensure Event Viewer (Local) is highlighted in the left pane and when it has read the data, expand Windows Logs - click on Application - Action/Find then type chkdsk or wininit into the Find box and press enter.
Cancel the Find box and read the report in the scrollable window.
Also, check Event Viewer for any time stamped Errors for when you got this error.
To view those, click on Error then on Show All Instances of This Event in the lower right pane.