Looking for help with the following problem. Last week, I updated my Powerbook G4 to 10.4.10 and since then the system fails to boot. The failure may or may not be linked to the update, but the timing is suspicious.

When I attempt to book the system, it hangs with the spinning daisy wheel at the gray screen with the apple logo. It won't boot from the Tiger install DVD; doesn't seem to get as far as looking for the DVD.

If I boot into single user mode and run fsck -fy, the command reports a number of block count errors when checking the catalog file and then fails while a "disk0s3: I/O error. Invalid key length (4, 20821).

I don't want to lose the data in disk if at all possible and I'd like to know;
(a) can this be repaired using a more powerful disk utility such as DiskWarrior?
(b) is this worth taking to the Genuis Bar for further work?