++< For ease of reading:
A) Wii U Premium 32GB Pack - Black with Nintendo Land Game (Amazon)
B) Nintendo Wii Console (Blue) with Mario and Sonic at the London 2012 Olympic Games (Argos) >++
Hi there TantieTowie!
I rather admire the lad. Being helpful to his Mum and with clear goal in mind as to what he would like for Christmas, good for him! :)
The Wii U and the Wii are actually two different consoles, something that Nintendo have not been very good at all at communicating to their customers. Even the gaming press were confused when it first came out So the answer as to why B is a different price to A is because it A is a WiiU, the new console launched in 2012, whilst B is the old console originally launched in 2006. In tech speak, the WiiU is a whole "generation" more modern than the Wii. Without boring you with lots of nerdy numbers, the difference between the two devices is quite substantial. If this is your first Nintendo console for your home, I strongly recommend you go with the WiiU.
With a WiiU, you will get the WiiU Gamepad. This is a flat, Ipad-like controller with a camera, touchscreen and microphone, designed for games that don't suit the physical "flail about" input method. This means that the WiiU is a far more versatile console than the Wii, suited to lots of different kinds of games.Its what makes the WiiU completely unique compared to any other console on the market.
The WiiU is also "backwards compatible" with the Wii, which also means that you will be able to play any games which say on the box that they are made for a Wii, including second-hand games. The Wii will not able to play WiiU games, or use the WiiU Gamepad.
In the WiiU box you linked, you would get the console and gamepad, lots of cables and stands, and free game called Nintendo Land. To make the perfect present, I would recommend you get him another 1 or 2 games for variety. I can advise on what titles are currently popular, or, if you can tell me a little bit about your son's preferences and interests, I can come up with a more tailored list of suggestions. And if you have any more questions, please ask and I will do my best to answer them!