Time machine froze while formatting hard drive.

Question

I have an Iomega HDD 80GB USB 2.0 External Desktop Hard Drive. I have used this hard drive before on both my Mac and a PC, and it worked fine. The other day, I plugged in my external hard drive so that I could use it to back up my system on Time Machine. The external drive had some files on it already, so when I plugged it into my Mac, Time Machine said that I would have to format it. So I went ahead and allowed it to start formatting the disk, but then system preferences froze while it was formatting. I couldn't eject the drive so I had to force quit and restarted my computer. Then when I plugged in the external drive again, the computer said that it could not read the disk. So I opened Disk Utility and tried to reformat the hard drive. However, Disk Utility froze about a minute after it started reformatting the external hard drive, while the progress bar was on "Creating partition map". Once again, I had to force quit the application and I restarted my computer. Upon plugging my external hard drive in AGAIN, the computer said it could not read the disk so I tried reformatting the hard drive (through Disk Utility) yet another time, and it froze again. I tried this again and it froze again. I tried plugging the hard drive into a PC, and it did not show up in "My Computer." It did, however, show up in Device Manager, and Device Manager said that the device was working fine (I also checked all of the USB Root Hubs etc, as per the instructions in the Iomega support Answer ID 1235). So basically, the computer said the device had no problems, yet there was no way I could actually see any of the files on the disk (or format it) because it wasn't showing up in My Computer. And I can't seem to format it on my Mac because it freezes up every time.
Is there any way I can format this hard drive?? Is it corrupted and unusable? What are some other things I can try?
Edit: I also tried to reformat the drive by partitioning it in Disk Utility (following the directions on the Iomega support article) and Disk Utility froze when the progress bar said "Creating partition map."

Answer 1

A TM drive must be partitioned using GUID and formatted Mad OS Extended, Journaled. Do this:
Extended Hard Drive Preparation
1. Open Disk Utility in your Utilities folder. If you need to reformat your startup volume, then you must boot from your OS X Installer Disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Installer menu (Utilities menu for Tiger or Leopard.
2. After DU loads select your hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Note the SMART status of the drive in DU's status area. If it does not say "Verified" then the drive is failing or has failed and will need replacing. SMART info will not be reported on external drives. Otherwise, click on the Partition tab in the DU main window.
3. Set the number of partitions from the drop down menu (use 1 partition unless you wish to make more.) Set the format type to Mac OS Extended (Journaled.) Click on the Options button, set the partition scheme to GUID (only required for Intel Macs) then click on the OK button. Click on the Partition button and wait until the process has completed.
4. Select the volume you just created (this is the sub-entry under the drive entry) from the left side list. Click on the Erase tab in the DU main window.
5. Set the format type to Mac OS Extended (Journaled.) Click on the Options button, check the button for Zero Data and click on OK to return to the Erase window.
6. Click on the Erase button. The format process can take up to several hours depending upon the drive size.
If you want to use the drive on Windows you will need to create two partitions rather than one. After performing the partitioning set one partition for Mac OS Extended, Journaled and the other for MS-DOS. TM will backup to the OS X partition. A TM backup volume should be at least twice the capacity of the drive it backs up, so be sure the OS X partition you create is large enough to use for TM. The remainder of the drive's space can then be allocated for a Windows volume.