Sounds like a failed hibernate.
The following should work:
Get to a command prompt
You can try hitting F8 while but I don't think this will work.
You'll have better luck booting from a USB floppy drive with a DOS boot disk. You might have success formatting a usb flash drive as a system disk.
Then delete the file hibersomething.sys It should be equivalent in size to the amount of ram you have.
Without that file, your reboot should go smoothly.