Ok,

I really feel like a Windows user now...I just tried installing it (to run ONE PC program) after no luck with Parallels.

AND IT FAILED (Boot camp install kept looping - I QUIT with F3), and now I can't boot into ANYTHING.

I just have the chime and a blank grey screen.

I tried Target disk mode, install discs, Leopard disc. NOTHING. Just allows me to eject discs.

Someone please have a solution, other than APPLE repair?

Hold down Option when turning it on and select your Mac partition.

Well... first things first, try booting while holding down the ALT/option key on your keyboard. That should give you a list of bootable devices (CD/DVDs inserted as well as any bootable partitions on your hard drive).

It gave me the arrow cursor, and then froze.

I have an external FW400 boot disk connected as well now.
Will try again with install discs.

DO I hold option and then power up, or press power and then hold option?

How long do I have to hold option for?
It froze again 10 seconds after cursor appears.

During the Boot Camp (Windows setup process), it kept asking me to format drive C (not enough space etc).
Partition was 5GB Windows (default).

Either is fine as long as you hold it quickly after turning it on. Hold it until you see the Startup Manager appear. On Intel Macs it only takes a few seconds.

Startup Manager isn't appearing.

Just the arrow cursor after 5 seconds, then it freezes after another 10 seconds.

If I have the external boot drive hooked up, should that kick in automatically (as with Macs)? FW400 or 800 make any difference?

My fear is that the internal drive was reformatted by Windows, and now has nothing on it.

Is my only option to try and resume the Windows install somehow?
I only tried holding C to boot from optical disc earlier - but nothing happened.

I bet you're not holding the C or Option keys soon enough. You can't break that functionality since it's part of the firmware. Try holding Option before turning it on.

Yumbo,

Sometimes a little patience is golden. When you boot with the option key down to invoke the Startup Manager, it takes a bit for the computer to scan around looking for bootable devices. I've even seen it take upwards of a minute or a little more. Your bootable devices will show up in the screen, and the computer will keep looking for a bit (and the cursor will spin) and finally it will relinquish control to you, and you choose one and hit the return. If you attach a firewire drive, either fw400 or fw800 is fine, it will show up in the Startup Manager, too.

If your external FW drive is truly a startup drive (clone of internal drive, pre-boot camp would be preferable), and was formatted HFS+ with a GUID partition map (needed to be an intel boot drive), then it will show up in the Startup Manager and you can select it and boot from it.

Also, with this:

I just have the chime and a blank grey screen.SOmetimes when you have a system glitch, or do a hard reboot, the Mac runs some diagnostics and file system checks for a minute or two, and all you see is a grey screen at the beginning of the startup sequence. Again, be patient and let the grey screen run for a bit before you decide you've hosed the startup drive.

As mentioned above, if you put in the startup DVD that came with your iMac, and restart the computer, holding the "C" key down, it will force the Mac to boot off of the optical drive. Again, be patient, and let the computer do its thing (hold it down a minute or two, at least, until you see evidence of boot).

You haven't talked about how you were trying to do the Boot Camp install, or how it failed, so some more info would give us some clues as to what happened. Also, the application you were using in Parallels, what was it? And why do you think it wouldn't work? Parallels has become very robust of late.

ok,

It brought up the external boot drive!
But when I click on it (the grey on screen arrow in a circle pointing to drive), it freezes after about 10 seconds.

Is freezing a common thing in this instance?

I put in the Leopard disc and tried again (hold option before power up) - gave the initial cursor only and then froze.

ok,

it brought the external boot drive!

But when I click on it, it seems to be frozen.Be patient and wait until SM has done its thing. The icon will show up before it relinquishes control to you. Once the cursor quits spinning, you can select and reboot.

Cursor does not spin at all. Remains as arrow, then freezes.

Is the reboot automatic, after clicking on drive?

A couple of notes... On Intel Macs the Startup Manager is much faster than PowerPC Macs. I've never had to wait for it to scan the computer for bootable devices. PowerPC Macs with Open Firmware take a while because they always do a search for a NetBoot server. Intel Macs with EFi do not search for NetBoot servers. I don't think I've ever waited more than a few seconds, even with multiple external drives and an install DVD inserted.

Second, you can boot an Intel Mac with a APM formatted drive. You can not, however, boot a PowerPC Mac with a GUID formatted drive.

Yumbo, please explain exactly what you're seeing. What cursor? What does the background look like?

Is the reboot automatic, after clicking on drive?No. Hit the return key.

Jason is right. I forgot the Intel Macs with EFI scan much quicker than PPC Macs with OF.

No. Hit the return key.

Or click the up arrow beneath the selected volume.

The black arrow.

A friend suggested OPTION-S, which caused the external to boot immediately.
Showed that internal drive was windows corrupted (if you ask me).

NEVER AGAIN.
Now I have to re-install everything.

Thanks for all the insight!

Finally got Parallels running today with Windows XP off an ISO.

Ran the PC program which is out of date after all. That's all she wrote.