registry falure, getting blue screened on boot up

i've got a problem. my computer is refusing to boot up. everything was fine up until today. i turned on my machine and after the win2k load up screen i get the dreaded blue screen with the following message:

STOP: C0000218 {Registry file failure}
The registry cannot load the hive (file):
\systemroot\system32\config\SOFTWARE
or its log or alternate
It is corrupt, absent, or not writable.

i tried inserting my win2k CD to reinstall the OS but it wont even allow me to get to the CD boot screen, it just blue screens me right after the win2k load up screen. i figured this was because the primary boot device was set to SCSI in the BIOS because im using my SATA drive as primary. so i went into the BIOS and change the primary boot device to CDROM, now the win2k cd setup loads fine, but my SATA drive no longer shows up in the list of drives in the win2k setup, so i cant fix the drive that has the problem. only my secondary IDE drive shows up. so i thought let me install it on that anyway and maybe i can get to my SATA drive that way, but after installing win2k on the secondary IDE drive and booting up, my SATA drive doesnt show up in my computer, and if i go back into BIOS and put the SATA drive as primary boot, i'll get the blue screen again.

i dont know what i did to get here, but i could really do with some help on fixing it. i have so much work on my SATA drive that i cant bear thinking about losing it.

 

If you can tell me the maker and model of the controller for your SATA ports, I can help you. Is it on your motherboard? If so, the motherboard model will suffice. Also, get a clean formatted floppy disk ready once you post this info for me.