In any case, I'm writting this because the only solutions on the internet I found required using your windows install cd to go into recover console mode... and follow the procedures from there.
That seemed like a PITA, so I am posting an alternative solution which worked great on my system...
The driver for the stupid backdoor is called "hxdefdrv.sys", and it sits in your "c:\windows" directory. There will most likely be an entry labeled "c:\windows\svhost.exe -sr -l0" in your run and run once key in the registry. You will noticed that you won't be able to find svhost.exe because it's been hidden by the bastard.
My solution was to look for the actual backdoor on the net. I downloaded it. It's a file called "hxdef100.zip", which actually HAS a command line uninstall which removes memory resident aspects of the backdoor. I had to go to the command prompt and enter "hxdef100 svhost.exe -:uninstall". This will make it such that you can actually delete "hxdefdrv.sys" without it magically reappearing after boot. Upon reboot, you should bring up the task manager and kill the "svhost.exe" process (not svchost.exe), and make sure to delete any entries that reappear in your run/run once reg keys. You will also notice a few more files in your "c:\windows" directory. The 3 biggies are svhost.exe (not svchost.exe), winunins.exe, winunins.ini. These are just some of the bastards that were cloaked. If you look in the "winunins.ini" file, you'll see the config for the backdoor.. listed in there are other files you should search for and delete if you find them, as well as the hackerdefender100 reg keys (which should be deleted as well). You'll also see the config for scanners and what not this backdoor is set to bypass.
Argh! don't people have anything better to do with their time? I hope this helps anyone in the same situation. It's taken up most of my morning dealing with this stupid crap... ARGH!
