|The message seems to indicate your hard drive may have failed. |
First try booting into the BIOS (setup) screens using the onscreen prompts. See if the hard drive is showing properly there. If not then try the following.
Most hard drive manufacturers have a drive fitness utility available. If you happen to know the manufacturer of your hard drive download the utility and burn to CD. Then boot to the CD to test the drive. If you don't know the manufacturer then try using the one from Hitachi. I am told it will work on any brand. Better to use the dedicated utility if possible.
If the drive shows OK in the BIOS then your operating system may just be corrupted. You may need at that point to attempt a repair or new install.
I can't help you with that as I know little to nothing about Macs.