At one time we went to some lengths to try and "save" such drives, as they were very expensive. One possible way is to save what you can, and then reformat the drive. Using the Windows "Format" program, this will flag and ignore damaged sectors. However, such a drive can be very unreliable indeed, it depends on the damage. If a head has actually crashed, ( A "head crash" is when a head actually touches the surface of a disc. Normally it should never do so, but float above it ).
Formatting it may help, or it may not. If you still get read and write errors after formatting, and running a few tests, by moving a few files back and forth, then the disk is basically junk.