1) Awesome!! My kids live MineCraft
2) point of the game - technically it is to kill the Ender Dragon.
3). Not sure why I know point #2
I spent a couple months last year playing Minecraft heavily with my boy. When I finally killed the Ender Dragon in "hardcore mode" -- where the game ends when you die once -- my son and his friends looked at me like I'd come down the mountain carrying the Ten Commandments. They think I'm at least a demigod now.