Well, look, the mouse doesn't work in the game; you have to use the arrow keys on your keyboard to move around and press Enter to interact with the game. You can also change the controls within the game to make it more comfortable for you.
To enlarge the game window, go to Options, Video, and then Resolution. Use the arrows on your keyboard to increase the size. If you want it in full screen, go to Video and change "window" to "full." That's it! I hope this helps.
