Steve,
I have a Wii and I also have the new Kinect from Microsoft, I would say try the Kinect first and you will see that the Wii feels a little old hat. With Kinect there are no controllers and you can get the sports or adventures and Joyride is great.
If you can try one, there is nothing else on the market like it.
If it's not for you then sports and mario kart is great over christmas
