i tryed the command before typing ''startx'' just type ''fixvesa'' it will work.good luck.
sorry to post after so long, but I am having the same issue after installing Backtrack as the sole operating system on my thinkpad. After installation I can login using root:toor and it gives me the root prompt and the option to type startx to start the gui. I get a solid cursor that never goes away if I type startx. if I attempt to navigate away from root I get "No such file or directory." when I type ls, the only folder I can navigate to is "Desktop" I can't access the hard drive at all to attempt to edit the grub file in that awesome tut that nmiller0113 posted.
Thank you for all your assistance.