Advice about the current state of the game and classes .

Hi guys . I know this is probably a very frequently asked question , I played Classic for a while since it came out . And now I want to try TBC . Is the games still active ?I want to know what's the best EU servers ? That have a good population and a good community . Also I'm interested in what's the most fun classes in TBC in your opinion ? I was thinking maybe paladin or warrior or shaman . Since I usually play Warlock .