I you press Alt+Enter on Windows, it changes to windowed mode. Once in windowed mode, you can drag it onto the correct monitor, and then press Alt+Enter again to go back to fullscreen mode.
If you wish you can also adjust the resolution to fit your goggles.
You change the resolution by adding command line parameters to the exe file as described in the manual. For example:
-screen-fullscreen 0 -screen-width 800 -screen-height 400
(That will run the simulator in a 800x400 window)
To be able to select different displays you might also be able to use the -adapter command line argument. Have a look at the Unity Standalone Player command line arguments here:
https://docs.unity3d.com/Manual/CommandLineArguments.html
(Under "Unity Standalone Player command line arguments")