Debian Admin published a guide about booting debian in text mode instead of graphical mode
Howto Boot debian in text mode instead of graphical mode (GUI)
You can prevent automatic running of the GUI when you boot your debian machine by disabling your login manager be it KDM, GDM or XDM from running at boot time. To disable the login manager from automatically running at boot up.
Howto Boot debian in text mode instead of graphical mode (GUI)
