You're not going to see new games on this list. I am the type to latch onto stuff I really like. Plus, I don't devote much time to playing.
Neverwinter Nights - you can get the Diamond edition on GOG cheaply. I play it LAN-style with my kids, who enjoy it. I also play on a Persistent World. And I'm working on a module in the Aurora Toolkit. Oh, and I'm playing it on Lubuntu, though the kids use Windows 7 or XP, depending on the box.
FIFA13 for the XBox 360. I hate the direction that console games like this are going, with online play being the only real venue. But there is a career mode that I'm enjoying. The AI is good enough for me, and I'm slowly getting the hang of the 15 million different commands (I'm an old 8-bit button masher at heart).
Diplomacy, both via http://www.webdiplomacy.net/ and an Android app called Droidippy. Not sure how I avoided this game for so long, but I'm enamored with it.
Forza 4 and F1 2012, also for the XBox 360. I would love to be able to race the IndyCar in Forza 5, but as I already mentioned, I just can't bring myself to upgrade to a game whose primary selling points are all from online play. But those two are quite playable.
After re-reading the question, I realized that it doesn't limit to electronic games, so here are a couple more:
Dungeons and Dragons 3.5E in the Forgotten Realms. Yeah, I'm running a campaign for my kids. They're about to meet a group of drow for the first time. I smell a TPK coming.
Agricola (plus other German-style games). That one has my attention lately, and is probably the newest game on this list. It's similar in some respects to Puerto Rico, but I've found it more interesting.