Hard drive failure. Hi. My hard drive stopped working and will not reformat or reboot. The cd

Question

Hi. My hard drive stopped working and will not reformat or reboot. The cd tray will not open either. I bought a new 80 gig IDE hard drive (Western Digital WD800BB) to swap out with the existing, but the unit will still not work. I only get "hello" on the unit and the background RCA screen on the TV with no menu.

Any suggestions? Thanks so much!