How to re-install OS 10.3 (Panther)?

I've recently erased partitions and re-installed OS 3 a few times, after disk errors such as

Checking extents overflow file

invalid key length

volume check failed

Error: The underlying task reported failure on exit (-9972)

and

keys out of order

The machine was working fine (I just want to use it to watch DVDs) and I powered it down. (Hmm, I might have just turned off the power switch rather than logging out, etc.)

Then, when I turned the machine on again, as far as hard drives go, "MacIntosh HD" disappeared and an unmounted "disk03" appeared when I went to Disk Utility on the Install CD, seeking to repair the disk.

Now, when I boot the machine with the install disk inside, holding down the C key, there's no place at which to reinstall the OS. When I go to Disk Utility, there's only a circling circle with the message "Gathering disk information" which goes on without success.

What to do?

Thanks for any suggestions.