Wii or Wii U Console
The Wii Mini is not yet supported.

New Super Mario Bros. Wii game disc (or a ROM dump if you'll be playing with Dolphin Emulator).

SD or SDHC card (if you'll be playing on a Wii) or SD card (if you'll be playing on a Wii U) with at least 570 MB of free space, formatted to FAT.

A way to access SD/SDHC cards from your computer.