You can play some Xbox games on the 360 but on April 14th Microsoft will be ending that feature for Xbox live but you will still be able to play them off line. go to Xbox.com to find the list of games that you can play.
it plays some old xbox games
No, its a totally different format.
All of the Xbox 360s may play games. They are priced differently because of either memory space or package deals.
Only if you have the Xbox 360 hardrive and some software.
No because XBOX and XBOX 360s are different from Windows 7.
No. NTSC games will not work on a PAL Xbox 360.
Hell naw
No. Xbox Originals are original games from the first xbox that can be downloaded on your xbox 360
All Xbox 360s can play all the Original Xbox Games on this list http://www.xbox.com/en-US/games/backwardcompatibilitygameslist.htm provided that you have an Xbox 360 Hard Drive and can update the game with Xbox Live or through a computer and USB flash drives or DVD/CDs
all xbox 360 controllers are compatible with all xbox 360s
Buy 2 xbox 360s and put a cable between them.
All Xbox 360s.