With that description I think u have quite a few :)
Dragon tavern - www.dragontavern.com - might be one of them. Lots of classes to choose from, u start with 25 turns per day (replenish every 24 hours at 10:00 GMT) and it's all about kill and gaining XP (u can train several things).
Gladiatus is also a kind of RPG but directed to PvP combat (try it out and see if u like it)
Fallensword is also an option but you don't have classes to choose from.
Also take a look at the Free browser list that is at this browser games sub forum
