Failload455

I have a Western Digital 500gb external hard drive, with 2 partitions, 'KAINARC' and 'JUNGLEMAC', connected to my Intelmac (Tiger 10.4.11 via my firewire, i have connected via usb but the problem is still the same). I may have shut down the drive improperly to cause this situation.
KAINARC now appears on my desktop, but the partition of JUNGLEMAC does not. I go to disk utility and both partitions are visable, KAINARC is mounted but JUNGLEMAC is not. I cannot mount JUNGLEMAC.
When i try to verify and repair the partition I get the message:
Verify and Repair disk “JUNGLEMAC”
Error: The underlying task reported failure on exit
1 non HFS volume checked
1 volume could not be repaired because of an error
So I try to verify and repair the partition KAINARC but get this message:
Verify and Repair disk “KAINARC”
Repairing disk failed with error Could not unmount disk
So I have opened diskwarrior (unbelievably long time to start up and scan disks) in the hope of fixing the hard drive, but when i try to repair I get the error message 'unable to unmount KAINARC'.
I have tried other repair/recover programs but get the same message: 'Could not unmount disk KAINARC'
Im asuming that to fix the hard drive it has to be able to unmount KAINARC.
Does anyone have any ideas of how I can fix this problem. I would normally reformat but I have a lot of stuff on the hard drive that I dont wont to lose.
chrisjay2001