I have to agree with ckamin, replacing the drive may be the best option. And certainly better and cheaper than involving the Geek Squad and then having a drive that you can't trust back in the system. The unfortunate truth is that XP itself is prone to screw up drives at times (we see plenty of reports of that here), so we can't be certain that there is a hardware issue with the drive, but we can't rule it out based on what you have told us. Getting a replacement hard drive may be best. You should also be able to buy a small inexpensive (less than $20, maybe less than $10) external USB self-powered case to hold the current drive. That would give you a nice external storage option. I would suggest that as long as the current drive seems to work that you use that space for regular backups of your new drive, a critical step when you use Windows that you seem to have skipped doing this time.