KE7GKP:
The wireless device you specified is Xbee, not "WiFi". Xbee will not talk to WiFi.
Now there IS a WiFi module in the same form-factor: http://www.sparkfun.com/products/10822
Both the joystick shield and the LCD shield want to be "on top". So you will need to rig up something to break that tie.
Thanks KE7GKP, I have updated my main thread with your link!
Do you think I should make use of another LCD shield and rather use push buttons?
The LCD screen should have at least 4 lines.
Appreciate your input!