Wii boots into a shell but when a game starts, it completely takes over. The menu you see when pressing the home button is not from the OS, it is called by the

Wii boots into a shell but when a game starts, it completely takes over. The menu you see when pressing the home button is not from the OS, it is called by the game into a linked library provided by Nintendo. Even shutting down the console by pressing the power off button had to be implemented by developers in order to be allowed to release.