well non graphic intensive and if you dont mind grinding cause well 90% of the mmorpgs is that. Try flyff or rappelz from gpotato. Or you could try city of heroes if you are willing to pay a monthly. Those are probably the least graphic intensive and somewhat fun ones that I know of. I am a wow head at heart so yea you should just stick with that one imo :P
Not Rappelz I mean try it n see if you like it, but *I* Wouldn't recommend it... I've found that their servers are completely unreliable (if you're on the US Server) and if it goes down, it takes DAYS to get back up... Not only that, but you can only get ahead by buying things out of pocket, and I don't believe mass pking of noobs is a fun time, especially when you're the noob trying to lvl lol... Like everytime I log in to the NON-PK server, there is always someone in the only place for me to do my grinding pking noobs.
However I haven't really found a lot of games that ISN'T like this... Conquer Online atleast gives you three noob maps where you can't pk noobs in but you can't get ahead without buying out of pocket (and expensive!!) points to get ahead, and once you're out of those pk-free maps, you're always getting pked while training...
I've found Divine Souls is a pretty good game, if you can handle the controls.. It just started it's open beta, free to play, beautiful graphics, and I've never been pk'ed as a noob. PLUS because of the open beta just opening last week, it also means you're not too far from the head of the line top-players
That's all I got, sorry for the rant LOL