Drives today don't actually get bad sectors like they used to because of problems with the making of the drive itself. However the filesystem usually get's corrupt, sometimes system crashes and maybe noise or motion like too loud of speaker system, 50dB is operational and 55dB is unoperational, or lets say you walk by it and it is disturbed.
Things like this aren't good for a drive.
Windows has a scan disk in XP, you right click on the partition you want to scan in explorer and go to properties you should be able to find it under the tab tools I think it is.
However it doesn't work great, it flags bad sectors and doesn't do a a repair.
I recently came accross some on a drive, so i recently found this program, it seems useful: HDD Regenerator
http://dposoft.net
If that continues for you, give that a try, seems quite useful.