If you want to just be able to log in as the one new user try this:
edit /etc/init.d/xsession and replace the line:
...
USER=knoppix
...
with USER=me

If you would like to allow different users or remote X logins you could try this, on my Morphix hd installs I apt-get install gdm (gnome display manager) and use it as the X login manager. Before gdm will work I have to make the Morphix xsession init script non-executable, so I " chmod a-x /etc/init.d/xsession " then when I bootup I can log in as the user I wish.

HTH

rock