Yes, all content on the Marketplace needs either a silver membership or gold membership in order to download content, also remember that one needs a connection to the Microsoft's Xbox Live servers in order to use Xbox Live at all.
Yes. It's the only way you can get it. I believe you need to have Xbox Live to buy it, because you can not get Minecraft as a retail version, so yes I believe you do need Xbox Live to get Minecraft.
no
No, you do not need xbox live you only need the points to play minecraft (1600-$20)
For Sure Every Game On XbOX Has Xbox Live
No, the Xbox version of Minecraft is for Xbox360
It is free at the xbox live arcade
Usually on Xbox live, all updates are free. So you won't need to pay for the updates.
To originally purchase Minecraft yes, but from then on it can be run without Live!
Yes, you need to be on live to use the Game Marketplace in order to buy Minecraft.
No, you get it over XBox Live.
No, it's a download from XBox Live.
Yes