

Keep in mind that if you use Right Control + f when in Full Screen mode, the screen will reduce to a window size revealing your MATE panel. To make it Full Screen, go to View and click on Switch to Full Screen.

The screen will now increase to a window in your Desktop. To do this, open Devices, go to CD/DVD Devices, tick the optical drive that you want to use and then click on Insert Guest Additions CD Image (or use your keyboard shortcut = Right Control + h). Once that is completed, you have to install the Guest Additions in the Guest operating system. When you first start VirtualBox and want to install a new operating system, the screen is small until the installation commences.
