Then I will try to make it easier for you. Start as usual except that at Grub menu, on the kernel command line add "init 3" at the end of the line (this will avoid to try to start kdm or gdm and make things easier for what follows), then you should end with a virtual console : a tty. There if you can see an invite to login, on a black screen, to login as root. : user root, hit enter, then type your root password, then hit enter.
Then type there: drakx11. If "task-X11" is not installed, it will ask you permission to install it. Proceed. Then you will get a blue ncurse interface to switch back : navigation is with arrows, and change option with space bar. (Hit space bar, seen how it reacts, hit up and down arrow, and fast you get to see how it goes).
Then you should be ok.
Don't do the test. Just validate your choices and try to restart.