What you could do in order to get a one time non-graphical login: When grub starts, go to the entry you want to boot and hit 'e', which should display the menu.lst configuration of this entry. Go to the "kernel" line and hit 'e' again to edit it. Just add a '3' (without the quotation marks) to the end of the line. Hit Enter and then press 'b' to boot. Et voila, runlevel 3
This only works once btw, once you reboot you'll go back to runlevel 5. So if you want a console login more than once in a row, you're better off editing /etc/inittab as shown above.