1. KotOR and TSL
With a rich and exciting story, combined with funny, interesting characters, what's not to love. The feat and force power systems were good, with loads of abilities to choose from. There is also the undeniable Star Wars feel to the universe, with a rich backstory. Oh, and there's HK-47...
2. Mass Effect 2
Proof that RPGs can be better wth more action and less micromanagement. The characters are fully fleshed out in an original universe, with unique aliens and a much darker story than the first. You can really feel that YOU are Sheperd and the impact of your actions play out through the story and by the use of the save import system. However, I prefer the Mako to the mining game
3. Dragon Age: Origins
The characters are the most layered and realistic characters I've ever seen in a game. It is possible to spend hours just talking to someone because you find them interesting and not a lot of games can pull that off. The combat is fun, but the most fun you can have is being a mage. There are a plethora of spells that range from turning someone to stone to making them explode, there are spells for all sorts of players. With loads of choices and possibiilties for the ending and a history that spans further and in more detail than almost all of the games I've seen, this game will definitely be one of the best RPGs in a long time.
4. Fable 2
Fable 2 is just fun. The story may seem very familiar if you've played the first one, but all of the things you can do make up for that. You can make so many different characters, from a corrupt, but kind hearted character; to a malevolent, sadistic, evil character. Rather than just the good/evil morality from the first one, there are now two: good/evil and pure/corrupt. This opens more possibilities to actually play a role, something that some RPGs miss out.
5. Oblivion
The world in Oblivion is huge. I'm talking really huge. You could spend ages trekking from one town to another... Until you find the fast travel system, that is. There are so many quests in Oblivion, that I challenge you to finish all of them. I personally like the Dark Brotherhood quests and the main story was very good, too. There are loads of weapons and armour, and I don't know how many spells there are, but there are a lot. The main fault I can find with this game is that there isn't enough choice. I expect most missions in an RPG to have at least two outcomes.