[Haskell-beginners] State, StateT, or ST for game settings?

I would like to create a game with a "main menu" offering the user a choice of "playing the game" or accessing a "settings menu," in which he can change defaults that would affect the game play (e.g. board size, etc.). I know (barely) enough about the "IO monad" to write the menus and the basic gameplay, but what device do I need in order to manage the settings? A State monad? A StateT monad transformer? An ST monad? None of the above? I have some basic familiarity with the first two, but not enough to really grasp how they are actually used.