I'm very inexperienced with Linux, and have been trying to set up an Ubuntu VM in Virtual Box.
I'd finally got it largely working, and then while reading about something I saw you could press alt+shift+F1 to open a TTY. I had no idea what that was, so I tried it.
It shrunk the screen, and put me at a shell asking for my password. If I gave an incorrect password it complained, but if I have the correct password it just sat there and did nothing. I could enter no more commands. If I hit ctrl+c, it would bring me back to asking for password.
Eventually I got frustrated and forced the VM off. When I rebooted, there was a bunch of odd behavior. The launcher wasn't working at all, and the second monitor had nasty ghosting effects where it would only display things as I moused over them, and then they'd be stuck there; if I resize the screen, it would end up totally black until I e.g. moved a window into it or right clicked.
I've made a video to demonstrate the problems I'm having: http://youtu.be/Ys8mNzCcJ6Q
It's worth noting that the shadow for the menu bar appears, and when I press super the shadow disappears as if the launcher was opened; additionally, I can type e.g. 'display' and press enter to open the display menu.