You will need to have several hardwares in order to play all the Wii games. The hardwares needed are based on the game that you want to play. Not all games need the same hardware and/or accessories, but let me list some hardwares and accessories that is available in the market now. As you might know, Wii now comes with various colours, to make it simple, I just put the white ones as examples.
(Wii Console)
* Needed for all the games. This is where all the fun starts :)
(Wii Remote)
* Needed for all the games. Some multiplayer games require more than one Wii Remote. Two AA batteries required
(Wii Nunchuk)
* Needed for some of the games. Some games are compatible with it to add extra control schemes to the player. Consider it as an addition to Wii Remote control. Used by connecting the wire from Wii Nunchuk to the Wii Remote. No battery required.
(Wii Classic Controller)
* An addition peripherals to Wii Remote to make it easier for games that requires rapid button pushing. Usually recommended but not required.
(Wii Balance Board)
* A wireless peripherals directly connected to Wii console wirelessly. It is usually required and/or recommended for sports and exercise games. Four AA batteries required.
(Wii Motion Plus)
* An addition peripherals to Wii Remote to make the remote more sensitive to movements. Some movement critical games consider Wii Motion Plus as requirements.
(Wii Remote Plus)
* The latest version of Wii Remote where it combines the Wii Remote and Wii Motion Plus in one. Players that already have this remote are not required to get the Wii Motion Plus for precision gameplay.
