Two ways:
1) Use DrakConf and change the boot mode there. Don't ask me exactly how, because I don't use that utility.
2) Use your favorite editor and edit the /etc/inittab file and change the following lines:
id:5:initdefault:
change to:
id:3:initdefault:
Now, if you're in run level 5 (graphical multi user mode) you can issue init 3 and you'll bring the system to run level three (command line multi user mode).
No need to reboot for these changes to take effect.