In reply to:

Group descriptors look bad... trying backup blocks...
fsck.ext2: Bad magic number in super-block while trying to open /dev/hda4

The superblock could not be read or does not describe a correct ext2
filesystem. If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>



Did you try its suggestion? 
fsck -b 8193 -f /dev/hda4
_________________________
Toby Speight
030103016 (80GB Mk2a, blue)
030102806 (0GB Mk2a, blue)