I spent some time but unfortunately I think the start up drive (which has the files I was after) has lost its functionality, hence the G4 twin mirror door would not boot.
I then replaced the battery but that did not solve the problem, although I think it was worthwhile.
I found some OSX system 10.3 disks, 4 in all - three black disks (1,2 & 3) and also a Unix disk. So I booted off the CD install disk, but I could not find a disk utility accessible on the install CD disk (or maybe its a DVD disk!!). So I did an install on one of the computer's drives - it has three separate drives. After the first disk installed (with an install option that did not delete the hard drive's contents), the install appeared to have finished, but then it went looking for drives, and it hung there.
So I used the start button to crash down the computer. I then found the reset button on the motherboard, which took my some considerable time! I then turned off the power supply by turning the power board switch off, I left the computer for some time and then I pushed the button, turned on the power switch power board switch (which only had the computer power lead on it) and then I turned on the duall mirror Power PC, leaving my finger pushing on the "C" key.
I thought what I had previously done wrong, was not put in the second CD/DVD disk, I thought the computer was perhaps not looking for a hard disk, but looking for the second install CD disk. But it wasn't, because it did another install, this time much faster as it did not seem to over write the files that were previously installed, and the Mac (or was this one still a Macintosh?) then finished its install and restarted itself. Maybe the restart button allowed it do finish it's install properly? It never called on the other two black system 10.3 install disks.
So, it then successfully booted into 10.3. I changed the screen setup to find a resolution that did not have vertical stripes.
The computer has had I think OSX 10.5 on it, because the disk I used to install 10.3 on it, is a back up disk for Time Machine. And Time Machine did come until 10.5.
The machine is a twin CPU 1.25 Hz unit, with a 9000 64 MB GPU, and three of its four memory slots filled with 6200 RAM, two with 512, one with 256.
Darn - I had been looking forward to having a game of Strategic Conquest 3.01! 10.5 doesn't support Cassic apps. And I was not able to find system 9.22 on the machine.
Unfortunately the disk I am after, 10.3's disk utility was not able to recover it.
There are permission errors on two of the three disk drives. One is the original drive, and 160 MB drive. That has the data on it, and I am doubtful I will be able to recover it. I cannot even analyse the permissions on that folder.
I think my next approach will be to either find another hard disk, and install 10.5 on it, and then try to recover the contents of the failed drive using the Time Machine files. I am unsure how easy it will be to find a suitable drive. I am pretty sure the machine ran system 8 on it, but there is a drive called 7.5, maybe that drive came from an earlier Mac? The records say the dual mirror door shipped with system 9. I think I would have liked Time Machine as it would have backed up my father's files automatically, which he needed. I used to go around to his place and make Super Duper images, but I if I find some of those files, I'd need a disk to put them on!!
The good news was the monitor was working! However, there are various artefacts going on. I'll now pull the drives and the GPU out and air blow them and spray with some alcohol spray ... and hope that all works. The graphics card became crystal clear on one setting last night, after some time. After shutting down sand starting up today, the artifacts were back and didn't go a way, although above where the mouse pointer was, the screen had vertical lines, but above the level of the mouse pointer, the screen was fine. Strange ... the mouse is a $4 Burros mouse I bought yesterday. It's supposed to be compatible with OS X 10.3 and upwards. I don't know where any early mice have run too!
Thanks once gain for your help Amethyst1!!!