You need the Wii console and at least one Wii controller (you need 2 if you ever want to play with anyone)
And that's basically it apart from the games. You can get some pretty good bundle deals where you get the console, so many games and 1 or 2controllers for so much money. Definitely worth shopping round
This is the most basic package you can get
http://www.amazon.co.uk/Nintendo-Wi..._9?ie=UTF8&s=videogames&qid=1265324001&sr=8-9
Then you just build on that with the games you want and an extra controller or two.
Hope that helps.
Kelly.xx