Grothaal

Hi, There are so many titles. Wich one is best to get? I have been playing once and a while the demos, but I never can get immersed into the game, as I would like to. So, can someone give me an overview of the games, wich one is best to get, and how to play in in the sense of playing in multiplayer? I am downloading the 2.09 version rigth now. thanks