2 Player \ multi player game suggestions?

Hi there, Got two new rigs built as christmas presents for my wife and I - our old computers were falling apart . Looking for some suggestions of new games to play. We are looking for some new two / multi player games to really make use of the power of these new computers. Want to feel its worth the money spent

We were fairly heavily into Star Wars Galaxies till the nge hit and have been very on and off since then. Most of my existing games are two or three years old Dawn of War and Jedi academy are about my newest games

Basically the only games I would write off from the start are FPS just not her scene.

Im planning on getting oblivion just to see what the graphics cards can do, but as far as Im aware this is 1 player, and I dont really want to get heavily into a one player game as that can cause friction. My wife can be a very hard core gamer, but we just need a good large addictive game.

The rigs are identical spec

6600 Core2 duo processor
Abit ab9 pro motherboard
88000gtx graphics card
2gb OCZ PC7200 memory (5,5,5,15)
2x160gb sata hdd raid 0

So far Ive been very impressed with what the new card did to jedi academy and bitterly dissapointed with how little improvement there was to star wars galaxies. I really want us to be playing a game that makes these new systems seem worthwhile.

RTS games can be ok but tend to be short lived, at least the ones weve played in the past.