VNC Server - Now no login on server

[Bob Hartung]

Hi,
   I just set up F8 with all updates.  Edited the vnc config files, set 
password or a username, and managed to start vncserver.  When I connect 
from a remote machine all I get is a slate gray screen with a cursor (an 
"x" ) but nothing else.

Then I went into System -> Network -> Sharing and set it to share the 
desktop (here I was logged in as root).

Now after a reboot, I get a cli for login but am unable to log in to 
the machine.

so my questions
   1) is there a way to back out of the "Sharing" from the CLI?
   2) what is the command to give GRUB on boot to get me to the CLI?  I 
thought that it was "linux 3" but I must have entered it incorrectly.

TIA

Bob