Also, you should simply run the WD diagnostics utility to check the drive for errors.
http://support.wdc.com/product/download.asp?groupid=608&lang=en
I also recommend installing the free Acronis software. It allows you to:
a) make a compressed IMAGE BACKUP (backup Windows partition to another drive)
b) create a BOOT DISC to backup or restore (if main drive fails, replace, boot to backup and restore to new drive)