Change movie window size and location in DVD Player on Mac
You can change the size and location of the Viewer window.
In the DVD Player app on your Mac, do any of the following:
Resize the Viewer window: Drag the lower-right corner for a custom size, or choose a size from the View menu.
View full screen: Choose View > Enter Full Screen. If you have multiple displays, drag the Viewer window to the display you want to use before clicking the Full Screen button .
Minimize the Viewer window: Choose Window > Minimize, or press Command-M.