I think my hard drive is about to die, can I get some help?

Question

Hello!  Well, I have an iMac (I believe it's a mid 2007 model?) 20 inch, Core 2 Duo, and I believe my hard drive is failing.  It's a long story, but its more or less exactly how it played out, so bear with me.
I noticed a few things going wonky a little while back, and started to back up data piece by piece. Well, eventually, I decided the best thing to do was to find a way to back-up my important files (I would have simply made a bootable back-up image of my HD on my external drive, but I have too many video and audio files on there to risk losing should I make it a dedicated back-up drive). Well, in transferring my files into my external drive I received Finder Error -36 (or something, may have been 036). After researching the error, it seems it commonly pops up with one of two possible cases:
in transferring files between windows and mac formatted drives and causing an error, or
a potentially failing hard drive.
Fearing the worst, I ran a verify disk on Disk Utility, and it said the disk needed to be repaired. Booted from my DVD, and ran the Repair Disk. It said the disk could not be repaired, to make immediate back-ups, and reformat the drive.  Well, I hurried back over to mac to continue to attempt backing up my data to prepare for the reformat, the computer simply would no longer boot up the disk. It would go to the white screen and begin to boot, then immediately shut down. My BootCamp partition worked fine, however, except for a very similar transferring error. So I went ahead and reformatted (a quick one the first time) and Mac OS X refused to install (I am not sure if this was a DVD error as my optical drive is shot and very stubborn about reading a disc once I get one into the drive). I reformatted again, this time doing a 0 write out option.
After an excruciating week to reformat on a 0 write out, I installed Mac OS X (Leopard this time as to opposed Snow Leopard, in case it was a scratched disc). Well, thinking I had cured the problem, I tried to update to latest version, and upon doing so, encountered an error telling me the OS could not be updated. After rebooting the system, the computer seemed to go into a permanent status of a looped reboot. It would literally restart just as soon as the disk was loaded. So I reformatted again, installed Leopard, and ran disk utility. It told me that the disk could not be verified and needs to be repaired (after passing the verification test when booted from the DVD).  Now when I am on the mac, it is incredibly slow and sluggish, and takes anywhere from 15 minutes to an hour to load iTunes, or even check e-mail on Safari. This was cause for my original concern before the Finder Error I encountered and believed it was just ram dying, but decided to get a head start on backing up files in case it was something far more serious.  Is my hard drive simply dead and needs to be replaced, or is there something else I could do?  It is currently running basic Leopard from the install disc without further updates, as it seems updating the system tends to kill it.
Thanks for any help at all greatly appreciated.

Answer 1

To be honest your post is rambling and difficult to read due to the lack of proper punctuation I only read it part way however...
The first thing to do is a proper backup. Your system has Time Machine built into it, here is the Time Machine Tutorial. Look that over, get yourself an external HD to use as a TM drive and backup properly! This will backup all of OS X however it will NOT backup MS Windows!
If you think your HD is failing then run Apple Hardware Test in Extended Mode and if it reports errors you can post them here.
Roger