Blank screen w/cursor. Help!!

I restarted my computer a few days ago and after the loading bar screen it
just goes black with only my mouse cursor on screen which can be moved
around, but nothing else. I have tried every option under the F8 boot options
with the same result. Then, I tried using the Repair options using the disc.
Startup repair says no problems detected. System Restore says no restore
points are present, which is bull because I know for a fact there were quite
a few earlier. It also says that my computer is in a limited diagnostic
state. Chkdsk did nothing either. I need some REAL help with this as all of
the books I've browsed and other users only give half-handed answers and
"help".