I've played a lot of games this year ranging from Star Trek to Eclipse Phase. My game of the year in terms of enjoyment gained per work expended has got to be Advanced Dungeons and Dragons, the three hardcovers 1st edition. The more I play D&D the more enchanted I am by its role playing elements. I think much of the game development in rpgs since the 1970's has been in terms or developing better simulations- in other words, games that have more "realistic" qualities. D&D gives you a vaguely defined character in a vaguely defined world. The rest of the game is dependent on the enthusiasm of the players. The 1st edition is fairly difficult to make sense of right out of the box, but that's what friends and D&D contacts are for!
I have to mention the rerelease of Villains and Vigilantes. This is a superhero role playing game in which you play yourself, but with some randomly determined superpowers. The game features a simple and robust system for playing out super battles, flying, and throwing around cars and satellite dishes. I spent many an hour enjoying V&V back in the day. It's fun to have superpowers! As an aside, the powers are chosen randomly, thus this is not a game for people obsessed with every character being equal. One character is going to have super strength, one is going to be able to control squirrels. Make the best of it.