regedit HELP!!!!! deleted something

HELP!!!!!!!!! I was going through the regeditor and was
deleting some files of downloads that i had taken off
my computer already. In the process i must have deleted
something VERY IMPORTANT!! Now when I boot up,after
the windows xp screen nothing happens. MY screen is
black and thats the end of that. I can't get it to boot
in safe mode or anything. When i try to do a repair with
my cd, it ask for adm. password. I have no idea what
they want, We don't know of an adm. password. I know i
deleted something that had(
ooooooooHKEY /microsoft/current version/load)and also
(ooooooooHKEy/microsoft/currentversion/run)
i don't know if that helps and i know it had more then
that in it.. but i had found it under msconfig when i
was trying to stop some things from loading on start
up. i don't know if that is the problem or not. i have
a second puter with Xp on it. can i copy regedit files
from it and get them on other puter some home? thanks