I had head crash on my laptop. Lost some important emails.
The one thing I learned was if you get a head crash, don't screw around with it. Rescue everything off the disk as soon as possible, then chuck the thing.
A crash will wipe out a few sectors, yeah. But it causes tiny bits of the disk media (hopefully, not the heads themselves) to come lose inside the drive.
So now you have your own personal sandpaper floating around inside your drive. It's only a matter of time before it decides to randomly start wiping out other areas.
It is not a pleasant sound. We heard the one that stopped the disk cold. From two offices away.