Yes, Battlefield 1942 has a Multiplayer when you start the game and pick your player you should be able to click the "Multiplayer" button next to the Singleplayer button.
Yes, there are servers on Multiplayer that you can join on 1942.
Try installing the latest patch/updated for 1942 and install Punkbuster that should get it working :).
You have to be 13 years old to play on the multiplayer for Battlefield 3.
you cannot change or modify ONLINE game contect... ie playing online the server will kick you and/or ban you
No.
No it does not. All of its multiplayer capibilities are online only.
battlefield 1942 code for install
Yes.
If you mean the orignal battlefield game (Battlefield 1942), then no, you do not, it is a standalone game.
yes
There should be no blood in Battlefield 1942 at all unless playing a moded version.
Nope, it's only an expansion pack for multiplayer.