So, your video driver on ubuntu got screwed up and your screen looks like frell or is useless… time to perform an Ubuntu video driver repair. This is simple in most cases and you can try thye following:
Hit Ctrl+Alt+F1 when you get stuck at the “Boot Scripts” part, or even at the login screen. Give this a try even if the login screen doesn’t appear, but you think it’s there. You should then see a standard white text on black screen interface for terminal control.
Now, enter the following with subsequent authentication:
sudo dpkg-reconfigure xserver-xorg
Ubuntu should walk you through some easy to answer questions, using the arrows and tab key to navigate and accept or reject options. Enter the “sudo reboot” when it’s done and you should be good to go…