only the old ps3s can play ps2 games.
There are no Nintendo DS games that 'require' two people to play them, However several games have wifi compatability.
No, but certain Xbox games play in a Xbox 360 system.
Not all but most of them require internet connection.
Vizzed.com Downloading plugin is require
Play games, do the stock market, sell items in your shop, auction items, etc.
Android games require the Android system which is not available for the Mac. There are Android emulators but they are primarily for developers to create Android software on a Mac rather than an end user product.
You can play mini games to earn items, shop, battle, and adopt or play with your pet(s)
depends on your system. most xbox games will play on a 360
No, but some versions of the ps3 can play ps2 games
Most games for the iPad do not require wi-fi to play them.
play games to earn jewels .. at 175k jewels you will have all avatar items
No of course not PS3 games are for the PS3 system and do not play on the PS2