Its not the regular Ubuntu login screen and this happened just today. Can someone tell me why its different then yesterday? DId i download something accidentally so that it updated itself? More importantly, how can i bring back the regular Ubuntu login screen?
Run this command:
sudo dpkg-reconfigure lightdm
Apparently, for some reason, your default dm has been changed to gdm. You need to switch it back to lightdm.
Comment if it worked.