To make the VLC player movie screen bigger, click “Video” and select the screen you want from the list of normal size, half size, double-size, or “Fit to Screen.” You can also select “Fit to Screen” from the control panel below the screen. Click “Full Screen” for the largest size movie screen.
Press F11 to toggle the window between full screen and windowed view.
You can also use shortcuts to re-size to various preset values:
ALT+1 Quarter size
ALT+2 Half size
ALT+3 Original size
ALT+4 Double size
You can change the shortcuts by going to Tools>Preferences>Hotkeys.