reboot your system into single mode and add/remove users to your liking. You should not have to use the EBD. but you can.
With lilo-> Pass the parm: `linux single' when you boot up.
If you are using grub:
(This worked for me, but I don't have a standard config, LFS is great)
bootup-select the linux boot option but press 'e' NOT enter!
edit the kernel line then append single to the end of the line *not a new line*
when done press 'b' to boot the system.
Once you are in single mode, you may useradd root back in, edit your passwd file by hand 'root:x:0:0:root:/root:/bin/bash' is what you need, then change root's passwd by 'passwd root' follow the prompts and you should be OK.
Unless /etc/passwd is gone, or a null file then get one from a identical, or verry simmilar system and reset passwords.
if you can, read LAME
http://tldp.org/guides.html
Things not to do:
#rm -rf /
#rm /etc/passwd
don't root around!
Hope I helped.
