recover from bad directory


My hard drive has developed a bad block at the root directory I think; Carbon Copy Cloner said the problem was at /Volumes/Mc750/.
Disk Utility says its toast
I do have a few GUI options I can still try (Data Rescue and Drive Genius)

I would like to get something off it before reformatting or scrapping it. Looking at man fsck_hfs, it looks like fsck_hfs -r
might rebuild the directory tree. I'm not sure if it would work and I am unsure about the right way to complete the command; is it
fsck_hfs -r /Volumes/Mc750
fsck_hfs -r disk1s2 (using information from diskutil list) ?