Can I say the entire Elder Scrolls series? If not, I guess Skyrim would take the cake.
Superb voice acting, amazing graphics, massive quest lines and awesome DLC.
I always loved playing as a stealthy ranger build, using archery, daggers and light armor. I would always stalk the woods, day or night, looking for game and adventure. Then retire to the local pub for fine drink and song.
Oh, I miss good medieval fantasy games.