IMac Leopard Hard Drive--who knows what's the problem

Question

Alright, this all started last night. I downloaded some P2P programs and was downloading a few large files. I should have thought something was wrong when I got a message saying my start-up disk was too full and I needed to delete files. I figured I let it go overnight and see what happens. So I deleted some media files I've been meaning to.
This morning it had obviously restarted and was at the log in menu (though it shouldn't have). So I tried to log in. Then it kept going to white screen with grey apple and rolling thought thing underneath. It'd sit like that for awhile then reboot and get back to the white screen.
So I've been looking up other discussions and have tried the following.
--Hardware troubleshoot--restarted with power button, as it was coming on held down the D key--didn't do anything
--Disk Utility--inserted Leopard DVD, restarted held down the option button, Disk Utility. At first I couldn't unmount it. So I plugged in my old external HD and installed Leopard on it. Then through that external Leopard account accessed my IMac's HD. I couldn't get to the applications for some reason but was able to delete some if not most of the newly downloaded files I could find. Some I couldn't because of an error (-36) saying I couldn't read/write.
When I did Disk Utility on IMac from there I got error saying invalid ...count. Verify or Repair failed. I tried just Verify and it failed so apparently it didn't make it to repair.
So then I tried AppleJack program--downloaded and installed, then tried restarting. I'm not really positive I did the AppleJack program right. I restarted holding down the S button--got a lot of words and then it just stopped. When I tried to type applejack auto nothing happened so I restarted again. And then I couldn't start up on the external (the internal HD still does the white screen). It would give me a screen saying I needed to restart-so I did a few times and decided it was hopeless.
So now I'm re-installing Leopard on the external to hopefully at least have that access to the internal drive.
I feel like I've tried a lot but also wasn't able to do a lot of it. And I'm just hoping I haven't killed it past repair.

Answer 1

Hello,
*"--Disk Utility--inserted Leopard DVD, restarted held down the option button, Disk Utility."*
When booting from your restore disk, you have to hold down the C key until you see the Apple logo.
Then you can access Disk Utility from the Utilities Menu to verify and hopefully repair the disk.
"The log does have the same problem as my internal did with disk utility "invalid record count, Volume check failed" It also has 331 other lines I don't understand."
Reinstalling Leopard on a the disk with errors won't work.
If you have another Mac, you could try Transferring files between two computers using FireWire
If you have two Macs that are FireWire-equipped, you can connect them so that one of them appears as an external hard disk on the other. This is sometimes called Target Disk Mode.
To transfer files using FireWire:
Shut down the computer to be used as a disk. Leave the other computer on.
Connect the two computers with a FireWire cable.
Start up the computer to be used as a disk, then open System Preferences, click Startup Disk, and click Target Disk Mode. (Or, start it up while holding down the T key.)
A disk icon appears on the desktop of the other computer.
Transfer files by dragging them to and from the disk.
Eject the disk by dragging its icon to the Trash. (While you drag, the Trash icon changes to an Eject icon.)
On the computer you used as a disk, push the power button to shut it down, and then disconnect the FireWire cable.
If you can't repair the hard disk with Disk Utility, go here and check out DiskWarrior
Carolyn