My bad. You can use that method only from within Vista.
I think, your best bet is to slave the drive in another computer to backup your data and try clean install.
I'd check your hard drive first, though.
Run hard drive diagnostics:
http://www.tacktech.com/display.cfm?ttid=287Make sure, you select tool, which is appropriate for the brand of your hard drive.
Depending on the program, it'll create bootable floppy, or bootable CD.
If downloaded file is of
.iso type, use
ImgBurn:
http://www.imgburn.com/ to burn
.iso file to a CD (select "Write image file to disc" option), and make the CD bootable.
NOTE. If your hard drive is made by Toshiba, unfortunately, you're out of luck, because Toshiba doesn't provide any diagnostic tool.