Those registry entries change the startup option of the VSP service entry in Current Control Set and CCS002. That alone would not cause an inability to start the recovery console, which starts before the OS. You can still boot to recovery console off an Operating System CD later than NT3 (Windows 2000 or XP, maybe the server OS #1 install disk too, I can't remember).
Assuming you can get on the Internet, google "Recovery Console" and you'll get to a place where you can find all the RC commands.
It may be that you'll have to do a parallel install of the OS to get at your data.
I too have had techs trash my system, including once a Microsoft tech, and THAT'S annoying when you've paid $245 for a support call. You have my sympathies.