tamaranth | help on borked filesystem on external drive

Can anyone recommend a utility to fix a borked file system on an external drive?

Background:
- have finally got around to connecting my three external drives to groovy werk-perk laptop
----- drive #1 (Iomega 120G, circa 2000) no work. Not even power. Bye-bye, drive #1
----- drive #2 (unbranded eBay-sourced, 120G, circa 2004) is fine and happy. Though occasionally hiccups and tells Windows it's not there any more. (Windows is stupid enough to believe this even though it is happily writing stuff to and from drive.)
----- drive #3 (same as drive #2 but possibly slightly older or younger) is sulking. It's the one I used to back up my old WIndows desktop after the 'reinstalling XP' hate-fest which ended up with DLL errors in the setup. There's stuff in the My Documents and Desktop folders that I'd like back, but it won't give. DOS tells me 'invalid directory' on these. Windows just searches forlornly -- or, when asked to copy whole directories, claims 'I/O error reading from source device'.

I'd quite like my files back, drive #3. Can anyone advise? (There is clearly nothing desperately urgent since I haven't had those files for nearly a year. But there is History there, and probably some embarrassing photos too.)