What exactly is the difference between X box arcade, X box 360 and X box Pro [Besides the Hdd storage space] ???
I think you mean the Xbox 360 Arcade, Xbox 360 Pro or Xbox 360 Elite? I don't think you can buy a regular Xbox 360 anymore (think it was renamed to Arcade). The only difference I know of is on the Pro and Elite it has the metal plate on the disk drive and with the Elite you get a HDMI cable.
Arcade – no hard drive, no headset and just a composite cable (you need to buy a component, vga or hdmi cable to use on your HDTV) You do get a wireless controller, 256MB memory card and DVD with the full versions of Pacman Championship Edition, Uno, Boom Boom Rocket, Feeding Frenzy and Luxor 2. Pro – 60gig hard drive, wireless controller, headset, network cable, Component and Composite Cable. The DVD drive has a silver bezel too. Elite – The 360 is black, you get a HDMI cable, wireless controller, headset, network cable and a 120gig hard drive. That’s what I remember from the top of my head anyway, if I’ve missed something let me know.
While we on the topic, the Headset that you get what exactly can this be used for, is it like only for specific games that you can use this for??
Voice chat over Xbox Live / LAN games, any game with multiplayer will support voice chat. Even games that don’t have multiplayer you can still bring up the Xbox guide and start a voice chat when playing single player.
You can also use the headset as a phone headset It fits the plug and if your busy, just plug in your 360 headset into the phone, and there ya go