Boot Failure from Hard Disk

Hi,

Not to long ago I tried to boot my computer and it displayed the infamous "INSERT SYSTEM DISK AND PRESS ENTER" error. When I insert a hard drive that I know works and set it as the Master, and the non-working hard drive as Slave, then boot, the hard drive is accessible in Windows Explorer. All of my files are still in the same condition as they were before the hard drive failed. I tried using the Recovery Console on a Windows XP OEM disk to repair the Master Boot Record in case that was the problem, it wouldn't accept my administrator password. When I used the Ultimate Boot CD 4 Windows, I repaired the MBR (or at least UBCD4Win did), and the hard drive was still not bootable. The hard drive doesn't make any strange sounds at all. I could not find any helpful advice on HP Support, and I tried unplugging each device one-by-one until it booted.

My system specs:

Compaq Presario 6320US
AMD Athlon XP processor 2000+ operating at 1.67GHz
256MB DDR SDRAM Memory
60GB Ultra DMA Hard Drive
Integrated ProSavageDDR KM266 graphics with 32MB shared video memory
Microsoft Windows XP Home Edition SP2