I just want to say thank you and this did work. I repeat, this did work. A friend brought me their laptop running XP. This is the second time they were infected, but the first time I got my hands on their pc. I do not know if the BSOD on the safe mode was caused after the first infection or the second. I do know that I have had one heck of a time trying to find a SIMPLE solution through the hundreds of forum posts that I read. Prior to jumping on the forums I trying Kaspersky's Rescue disk which found Java files that were infected but did not clean the newest version of this virus by doing a complete scan.
Here's my experience with this solution.
1. I ran Kaspersky's Rescue disk, and once I got to the screen that would allow me to start a computer scan, I clicked on the program manager icon in the lower left and ran the terminal windows.
2. I then ran the windowsunlocker command as specified in your post and voila! it ran and told me windows was successfully unlocked.
3. I rebooted and tried safe mode, but again BSOD as expected since I haven't repaired any registry settings or files yet. However, I was able to boot normally and run the antivirus software without the FBI screen locking the computer. This PC had AVG installed already, and it claimed to have found and cleaned 2 infections.
4. I rebooted after the infections were "cleaned" and still BSOD on the safe mode boot, but on a regular boot I am not seeing the FBI locking screen any longer. It appears to have been resolved for now, however I will be using Malwarebytes and trying to get safe mode back, but at least I can work with that PC directly as opposed to being locked out completely.
Thank you again, I now learned a new feature on my Kaspersky disk (I am a big advocate of their rescue disk and was surprised it didn't come through on the computer scan).