...someone help me? i really need help
once i turn on my pc its a black screen
that tells me something about a boot disk
and then it says press Ctrl+Alt+Delete to restart computer
You could try to boot to your OS cd and do a repair then try once your at the c promt chkdsk/f command to try and do a repair on the bad sectors but sounds like it might be toast. You can always go into the bios and see if the hard drive even shows in there if not then its probably toast.
1. Try getting another hard drive and install a operation system on it then boot from it with the damage had drive in slave mode
2. Get a live cd eg. ubuntu then run it and then navigate to the broken hard drive.