Xbee, Wireless, Wifi, Bluetooth... What do I have to buy?

Bonjour,
Hello,

I start with Arduino but I already have made programming in C++, C, Matlab for my studies. I have read tutorials about Arduino for tha basis (input/output, LCD, Analogic read and write...) and I want to go further and enjoy with it! (As you certainly have noticed, English is not my native language so please when you answer, use simple word... Thank you!)

I'am commanding materials on a website in order to have a little bit of everything as components. Especially, I would want to start communication between my Arduino Uno and my computer or other objects. (using bluetooth, Wireless, Wifi,...) but I'm confused and I dont know what to buy exactly. There is so much thing available!

Here is the list of what I found and that look like interresting. Could you tell me what is used for what, if it must absolutly be combined with other material, if several piece is needed ( one for the arduino, one for the PC or the other arduino...)? The webstite is in French, I hope you will understand by seeing the picture...

So there is the shield Wireless Proto

The module Xbee shield

http://www.gotronic.fr/art-module-xbee-shield-12427.htm

The module wifi Bee

http://www.gotronic.fr/art-module-wifi-bee-wls48188p-18935.htm

The module Bluetooth

For the shields compatible with arduino, I have the impression that we can make a big stack with them but in this case, do we have still access to all input/output or certain shields take some of them? Is there programming to add if you add a shield?

Here is some small modules that I have seen and which look like interresing but I do not know if they ask additionnal material to work:

Joystick (It looks we can add a bluetooth module, but in this case, 2 is needed no? one for the arduino and the other of the joystick)

Here a solar charger shield that look it must be stack on the arduino, but you think there is still as much input/output as before? and when it is stacked, it must be connected to the arduino supply?

http://www.gotronic.fr/art-module-chargeur-solaire-shield-sld80227p-18867.htm

So you have understand, I want to know what is needed for bluetooth, wirelesse, how really works a shield...
thank you in advance for all your answer!

Notice, by compute already has bluetooth, does it can help?
Do not hesitate to correct me about the work I use for all the material, it would help me to understand all differences...
I do not really need programming information, just what work with what!