there is a thread exactly to this,please see: http://www.escapistmagazine.com/forums/read/9.210766-A-good-totally-free-MMO?page=2
Anyway here is my list:
[HEADING=3]Runes of Magic [/HEADING]
better than wow IMO so far
[HEADING=3]Remnants of Skystone[/HEADING]
(broswer-based and platformer,steampunk world really awesome)
in a few months : Lord of the rings online;
Dungeons and Dragons online,altough I quit it for some reason I forgot.
[HEADING=1]EDIT[/HEADING]
Oh my god I forgot to read your post entirely.In Runes of Magic,once you reach level 10,you can choose your second class.You can be a mage/druid a druid/priest mage/priest anything you want. I made a mage/knight (knights are the paladins of RoM).
So yeah,this game will give you an awesome magic class.