I really don't know a lot about technical stuff, but I currently use
http://valid.canardpc.com/show_oc.php?id=1392644 and all my settings are at the highest except for shadows. (I kinda like hte circular shadows more then the realistic ones).
I think it's a reasonable good set-up, perhaps the graphics card is a bit older. But I run WoW absolutely fine on "ultra" settings on a 24" screen at 1920x1080.