I would expect that you need to configure your x-server. Boot again and log in as root rather than your user id, then try entering 'startx' (without the quotes) and either it should start into the desktop you expect, or it will flicker and then leave you back at the prompt (with some messages in between). If it puts you into the desktop, you can use the control centre to setup the boot into the x-server by default (under hardware->graphical server). If it does not work, there is a command line tool to set up the configuration file. Enter 'xf86config' and it will start you off. You need to know a few things lke the mouse type (IMPS/2 for wheel mouse), and the refresh rate of your monitor in the case that it is not in the list. If it doesnt work, you can always rerun the script.
Before you run the 'xf86config', copy the original so that you can move it back in case the problem is something else (to do this, 'cd /etc/X11' then 'cp XF86Config-4 XF86Config-4.bak').