Hi BlueDiamond,
From my perspective, none of the classes are "better" or "stronger" or "the best". It depends on your play style. You state that you've never played an RPG before, so try out the classes, see which is the best, then play on that one. Whats great about this game is that you can make a new character on that same account, and you can also reincarnate (Process of choosing a different class and restarting).
~balance