Boots to black screen

I have a Dell Desktop with service tag fgc3hh1. It a inspiron 518. We left for the day yesterday. When i went to boot it up this morning it shows the dell screen where i can push f2 for setup or f12 for boot menu. then goes to a black screen and never loads.

i have vista home premium'

i cannot boot in safe mode because it dont think the boot process goes as far as getting to the windows logo. I get the one boot screen then it goes to black . Lcd moniter still stay lit up and active.

what is the problem here?

Can you get into Setup? If you can, I believe it has a diagnostic for the hard drive. If so, run it.