In order to report a bug, you first must specify which GUI terminal emulator you have tried that did not work. With Mint 16 Xfce, you have the xfce4-terminal and x-terminal available installed by default, not to mention at least half a dozen different terminal emulators which are not native to Xfce4 which can be installed and work fine under Xfce.
I am inferring that you are running Linux Mint 16 Xfce with all updates from your OP, correct me if I am wrong.
Alternative methods to get to the CLI include the Ctrl-Alt-F4, etc., function key combinations, selecting from the menu, and running xterm or xfce4-terminal from the dialogue box after pressing the key combination Alt-F2. Have you tried all of them to see if some work and some don't?
LMDE Mate 64-bit, LM17.3 Cinnamon 64-bit
Debian Mate 64-bit, Xubuntu xenial 64-bit, Ubuntu-Mate 14.04 64-bit, Antergos Xfce 64-bit, PCLinuxOS Mate 64-bit