Help! I have a virus and malware nightmare.

It would probably help to give you a little backstory to explain how my laptop has become plagued. Alright, I am staying at a motel for the time being, and my laptop has been on the motel's default wireless connection. That is the basic backstory.

As of two days ago, it's like my laptop has caught the plague, so to speak. First off, I was hacked. I know this because there is another user who has ghosted themself into any connection I have used, including my internal network. Her computer is called Lydia-PC. I can get her MAC address, but her IP address is hidden. Should not have really been a big deal, ya know?

But then, I ended up contracting Buritos.exe and as you all know, that is the nightmare that wreaks utter havoc on your system and replicates itself. Along with that, I have contracted Karina.exe and the "Blue Joke Virus" (antivirus 2008 AND antivirus 2009). I have tried to do antivirus scans, but it has not worked. And the hacker was able to cover her tracks.

What has happened so far:

Permissions have been locked
Registry altered
Unknown directories
Bios has been altered
Boot.ini has been altered
Files duplicate themselves
It takes control while in exporer directories
Security has been completely been disabled as well.

I have tried to reformat my hard drive, but that did not work, as I did not have the permissions to do so. I have also tried a hard drive swap, but that was when I noticed that my BIOS had been altered. No, I do not have any scan logs, because I have been unable to perform any kind of scan whatsoever, due to security being disabled and my programs being locked. And there does not seem to be any way to remove Lydia-PC, either.

Do you have any suggestions or ideas as to what can be done, that does not involve completely trashing or rebuilding from scratch? This is driving me insane.