Something's Wrong with my Hard Drive

Question

I recently tried to install Ubuntu on my Intel Mac Mini. This ended in disaster and left my machine unable to re-boot into OS X. I finally figured out that I could bring up a boot menu by holding down the option key (derr). I then tried to partition my hard drive using Boot Camp so I could install Ubuntu that way. This caused an error message that told me to run the disk utility because my hard drive needed repair. Disk utility does not let me repair the hard drive, only verify it. I did this and it came up with the message:
Disk Utility stopped verifying “Macintosh HD” because the following error was encountered:
The underlying task reported failure on exit
in the dialog window it says: "Volume bit map needs minor repair" and "invalid volume free block count". I can only speculate as to what that means, the bottom line is that I can't partition my hard drive. I tried booting to the OS X startup DVD but the option key only brings up my hard drive as an option to boot to.
Any suggestions would be greatly appreciated, I'm stumped.
Mac Mini Intel   Mac OS X (10.4.10)  

Answer 1

I would just like to add that I ran a partition inspector and it came up with this result:
* Report for internal hard disk *
Current GPT partition table:
# Start LBA End LBA Type
1 40 409639 EFI System (FAT)
2 409640 234179463 Mac OS X HFS+
Current MBR partition table:
# A Start LBA End LBA Type
1 1 409639 ee EFI Protective
2 * 409640 234179463 af Mac OS X HFS+
MBR contents:
Boot Code: Unknown, but bootable
Partition at LBA 40:
Boot Code: None (Non-system disk message)
File System: FAT32
Listed in GPT as partition 1, type EFI System (FAT)
Partition at LBA 409640:
Boot Code: None
File System: HFS Extended (HFS+)
Listed in GPT as partition 2, type Mac OS X HFS+
Listed in MBR as partition 2, type af Mac OS X HFS+, active
I don't know if this will help, but it can't hurt.