you can get a jtag xbox from eBay
No, The jtag is only for modding, not banning and hacking
It means that you can put a Jtag on your Xbox (a hack) so that you can use unsupported files on the xbox system.
Don't buy a pre-jtagged Xbox. Jtag an Xbox yourself, it's much cheaper. If you're buying a jtag to host 'CoD Lobbies' then don't bother as you will be wasting your money.
Jtag is a mod for the Xbox 360 which allows you to play downloaded games. You could play xbox live with this but you will get caught and banned (xbox and gamertag ban).
YES
Yes unless you have a JTAG xbox that is unbannable
Key Vault for JTAG's to unban them
you will need a jtag
Yes
I have a jtag but and know you can on pc, it was also done on Xbox but I don't know how.
A JTAG IS A SYSTEM THAT IS ABLE TO DO THINGS LIKE ATOMATIC PRESTEGE OR GOD MODE or high jumping.
You need a special xbox called a jtag that is a modded xbox designed to hack games although Microsoft can detect Jtag hacks so its a matter of time until your banned from xbox live.