Try starting Vista in safe mode - keep tapping the F8 key when booting.
If nothing ever appears your lappie may have gone to the great lappie graveyard in the sky.
The hard drive may be fine tho'. It's possible to take a hard drive out, put it into an external enclosure, and get information off it with another computer.
Fingers crossed for you. Do you have a backup? If so you'll be fine anyway - if not, why not?