Cannot boot - even in single-user mode

[Handycam]

One of our iMac G4's refuses to boot up. It holds on the initial gray "apple" screen (without the round progress bar thing). This was after a 30-second-long neighborhood power failure.

OK, so I'm thinking a hard drive problem or corruption somewhere in the file system. So, following troubleshooting tips I found online, I boot into open firmware and reset everything. Then I try to boot into single-user mode to run fsck -fy. But here's where I'm stuck... I boot holding command-s, I get white text on the screen, but after a few lines of text the whole thing stops. I never get to a prompt, and cannot enter any commands. I need to unplug the mac to shut it off. Why won't it boot into single-user mode? Any ideas?

I also can't get the cd tray to open, I hold the eject key on the Apple keyboard, but nothing. And I know of no other way to get the tray open, so I cannot boot to a hardware test or install CD.

Any advice appreciated. Thanks.

[hayne]

Hook up a firewire disk with OS X installed on it and boot from that. (I think if you hold down Option, you'll get a choice of disks to boot from.)
Or it could be another Mac that you boot in firewire target disk mode (http://docs.info.apple.com/article.html?artnum=58583) so you can use it as a firewire disk.

One reason why you might not be able to boot into single-user mode is that some system file has gotten corrupted.
What's the last messages on the screen when you try to go into single-user mode?

And there's an 'eject' command in Open Firmware so maybe that would open the tray. Search these forums for the syntax - I know it's been mentioned before.

[yellow]

I also can't get the cd tray to open, I hold the eject key on the Apple keyboard, but nothing. And I know of no other way to get the tray open, so I cannot boot to a hardware test or install CD.

As hayne said, you can boot holding down Option, then you can open the tray with the eject key and insert the CD, click the circle arrow button (to rescan the buses), and select the CD once it shows up, and click the arrow pointing right.

[Handycam]

One reason why you might not be able to boot into single-user mode is that some system file has gotten corrupted. What's the last messages on the screen when you try to go into single-user mode?

The screen says:

IO kit Component Version 7.5:
RELEASE_PPC/iokit/RELEASE
21 prewired modules