ya so in an easier way to say it is
if your a Warrior/Monk you basicaly kill things and heal urself.
if your a Monk/Warrior you basicaly heal others and thats about it.
monks are always needed and will get you in groups faster, mesmers are fun to play cause they mess with other people. Necromancers can make minion armies and other cool stuff. Rangers can tame a pet or use his bow to kill things from afar. Elementalist (ele) can use the elements to kill things (fire is used most frequently). Warrior, well thats probably doesnt need explaining
so what ever you choose its fun, in the long run warriors and monks can make the most money with runs and 55ing, necros arnt bad either.
ask anymore questions and we'll be happy to answer