Ctrl+Alt+T doesn't open Terminal (Compiz related?)

You can click on the Shortcut combination showing in the System Settings -> Keyboard -> Shortcuts and reassign the key.

Hope this will help.

If you have compizconfig-settings-manager installed, you can reset the profile by going to the preference section of the program and clicking on Reset to defaults button.

You can try starting the terminal manually, e.g. from xterm and see what the output is.

Press Alt+F2 and then enter "xterm" to get an xterm.

There, simply type "GNOME Terminal" to try to start the terminal.

or try to edit the /etc/default/locale

Solution:'nano /etc/default/locale' back to the defaultc contents of that file to:

LANG="en_US.UTF-8"
LANGUAGE="en_US"