Suggestions for Multiplayer Gaming?

My best friend and I are fairly new to the multiplayer gaming scene and need a game that can run on both of our PC computers without causing significant lag on either end. My computer isn't the issue, it's the fact that my friend is playing on a 5-year-old laptop with a not-so-great graphics card, so we have to find a game with a "more generic" graphic card range so my friend can just put the game on a lower setting and it will run just fine.

Other than those specifications, we're both open to just about anything that isn't pricy (though we'll probably buy it if it's on sale either way). We're fans of RPGs and Action/Adventure games which is just about everything on PC, really. Any suggestions would be greatly appreciated, since we run through most games fairly quickly (we're already played Terraria, Amnesia: The Dark Descent, Minecraft, TF2 and some Magicka together and have gotten bored with/finished all of those)

Neverwinter Nights and Dungeon Siege come to mind.

Age of Empires 2, Unreal Tournament, Diablo 2, and Rise of Nations are the best games I've played VIA LAN.

We tried Rusty Hearts and were confused, so scrapped that. We also scrapped Dungeon Seige because of the cost (we can be cheap sometimes :P) Other than that, we're still looking stuff up for the others to make sure they'd be worth buying. Next on our list is Titan Quest right now, so we're probably going to try that soon.

Try Magicka awesome game to play in co-op with a friend my friend ran it with a 4350 or something weak like that.DJ_Headshot

We have actually played it, my friend can use one of their family member's laptops to play it, but it would crash (for whatever reason) and my friend wouldn't be able to rejoin the thing I was hosting and thus we'd have to start over. That's the only problem with that.

Also, we don't think Trine can run on my friend's computer either. Her graphics card is some brand I haven't even heard of and is really, really weak. Mine is 9500, but hers is the one she got with her 5 year-old laptop. I don't know specifics, but she can run Penumbra, a 2-year-old indie game and Oblivion. If that means anything. Neither of us really understand how these things work, but we try.