If it's WD Data Lifeguard bootable CD Extended Scan, I would try running it one or two more times to see if it can budge on repairs. If not, replace the HD.
You can also run Disk Check from Command Prompton DVD or Repair CD to see if it will repair file system enough that HD Repair scan will budge.
These two work together to repair a failing HD, although this one may already be a dead parrot.