Try Land of Magic. Its fun, with very little grind, a wide range of classes, skills and quests. At lvl 400 your charachter can be reborn keeping the old classes skills but getting another set of skills for the new class (i think). Its also just really dang fun!
Also try Crowns of Power, although it isn't a diablo 2 style mmo, it is low spec.
Lands of Magic is at: lom.neofun.com
crowns of power is at:
www.crownsofpower.com