No. In the first 6 Call of Duty games you can only play alone online, but in Call of Duty: Black Ops you can play split-screen online, but you can maximum be 2 players. Offline you can play with up to 4 players.
yes but two people have to sign in as guest
Yes, but they have to be in the same game and match.
redeem the code or do that guest thing
no
You can't play with each other on. The same console
Halo works but I'm not sure of others.
As long as both players have Xbox Live Gold you can play 2 seperate accounts on the same console on Zombies and Multiplayer.
no ps3 must play ps3 etc
I'm pretty sure you can... I know for sure you can on CoD BLOPs.
Depends what you mean. If your controller broke/died turn off the system, unplug/unsync the controller then turn on the console and plug in/resync new controller. If you mean how can 2 or more people play on the same console on LIVE/PSN it's not possible with Call of Duty. Only one person per console on LIVE/PSN. You can however make a private LAN server. Other games like Halo allow 1 or more people to use the same console and play on LIVE.
yes
Not on the same console..but you can play regular multiplayer (of course) and special ops (with up to 4 ppl i think)
Two on the same console and four online.
4 players can play through Xbox Live, but only 2 can play on the same Xbox 360 console.
two people can not play together on the same console on Red Dead Redemption.
No, no CoD supports this feature.