I love driving games. When I first sat down to Forza 1 I played for 24 hours straight and didn't even notice!
(FPS) FarCry 2 is pretty fun and the landscape is amazing. It has a very destructible environment and the weather is pretty unpredictable, you also have a day/night. They also added animals to the game, they arent very tough though.
I love the map editor, you can do so much with it. They really must have put a lot of time into developing the editor. I'd buy this game again. I dont like the way the controls feel, like just pulling the right stick to turn your character around is VERY slow compared to other games... and I set my controller sensitivity to max. The story-line is kinda dumb, enemies seem to appear out of nowhere, and you are sick with malaria throughout game play. The way the developer made the malaria sickness affect you has annoyed LOTS of gamers.
(RPG/FPS) If you ever played Oblivion then you have played Fallout 3. The plot, characters, controls, and the environment are so similar between the two games. They are so similar that many people have commented that Fallout 3 is just Oblivion with guns. I would agree.
Fallout 3 is really fun. There is so much to do, so many places to explore and things to find (guns, equipment, odd stuff, etc...). I've played this game through at least 8 times. I still find things in game that I had never seen before/done before. It can be difficult or easy depending on how you choose to "train" your guy and set the difficulty. Also my wife loves this game and she choose to buy the GOTY version so there would be more to do (I recommend the addons!). She also still plays the game.
(RPG)Oblivion is another of my all-time-favorites. Its immersive, well made, fun and difficult, and like Fallout 3 I still find places I've never seen before. If you've never played it or seen it, the game is set in a "medieval time" in another realm. Its all swords, bows, axes, magic, etc....
I've been playing this game for about 4 years now, I still love it. I had the GOTY on the PC and more recently we got it for the 360. The wife also likes this game, and she is the one to choose to get the GOTY version for the 360.
It has loads of mods I think you can still get (from marketplace) to expand the game, this is one of the best aspects of the game. Also it is a long game to play. The wife has played through the main quest over 10 times and recently did it again, it took her over a week an a half just for the main quest missions. Then there are all the other quests in the game which I would estimate add a minimum of 4 more weeks of play time.
Its a given that Forza is amazing!
(If you aren't familiar with what GOTY, Game-Of-The-Year... Its Bethseda's way of releasing a game with all their addons together in a disk pack.)