hmmm did u try doing the new prefix thing? also in my experience sometimes sertain configurations can cause some problem that can be fixed by running in a virtual desktop. you could try setting a virtual desktop with a resolution equal to your desktop resolution that SHOULD(at least for me....) make the virtualdesktop fullscreen so that you don't get the windowed mode effect... also what OS are u on? if its a 64bit OS make sure u have the 32bit opengl libraies installed(although i don't think you could make it to that screen if that was the case)(how to varies by distribution)
