It looks like you may have had a hard drive crash. Try tapping the F8 rhythmically and see if the safe start menu comes up; if not you most likely have crashed.
I have, on occasion, been able to resurrect a dead drive by placing it in the freezer for 12~24 hours and then putting it back in the machine but usually only works long enough to grab the my documents folder and the cabs from whichever email client is in use, then it's dirt nap time for the hardware. This approach requires having a rescue drive in hand and you have to work quickly.
