Always when preparing a game, I'm with the same question, and the games I do are "mini games" really, they are only to play for a short space of time.
If window mode is chosen, it will be easier to play while you are performing other tasks with your computer, but in full screen, is best seen details of the game.
Believe it or not, many games can be enjoyed best by choosing a windowed mode.
![Wink :wink:](./images/smilies/icon_wink.gif)