STOP: C0000218 {Registry File Failure}

I have a Compaq Presario V6120US Notebook PC with XP Home SP3 that just loops. It never gets to the logon screen. I can get the F8 to one screen only. The XP Disk doesn't do anything and Last known good config. does nothing, in fact, none of the options do anything. Any help? I've read the posts and the Malware post. All of that assumes that you can get past this point and don't really understand what their talking about anyway. HELP!!! I have mucho data I can't afford to lose.

STOP: C0000218 {Registry File Failure}
The registry cannot load the hive (file): \System Root \ System32 \ Config \Sam or its log or alternate. It is corrupt, absent or not writable.

 

When you say the XP disk doesn't do any thing, have you gone into the BIOS, (F2 key on startup, keep tapping), and put the CD/DVD boot first in sequence?
If it is an install of recover disk, your computer will boot from this first then. Try to repair from the options given.