My advice would be to acquire a bootable version of a Linux distro (of your choosing) and use that to boot your machine and then if you can still see you actual hard drive, immediately set about backing up your critical data to an external source (USB hard drive, or DVDs). Hope that it's not already too late.
Good luck and keep us posted.
Regards
Randy
Will it let you load the OS at all? Is so check your device manager for any problems with your hard disk.
Okay where do i find the BIOS?
If it's being seen. By the BIOS but can't boot even with smart off. This will sound weird but put it in a anti static bag and seal it well and put it in the freezer for about an hour. When removed make sure there's no condensation and plug it back in. The drive may then work for long enough to grab the files.