Dragon Age Origins is really good but like mentioned , isn't open world.
However , the story is A+ and if you like fairly straightforward old school RPGs, you'll like this.
Dragon Age Origins is probably my favorite RPG of the last 10 years or so. It's a micro-manage fantasy RPG, pause action, set some rounds of party commands, un-pause, and it's supposed to be much better on PC than on console. I personally think open world is a little on the overrated side, and prefer the heavily story driven RPG type gams that's why this is my favorite RPG.
DA:2 took away a lot of the micro-mange RPG aspects and made it more of an action oriented RPG and much more console friendly. I still enjoyed it, not as good as the first by a longshot, but a lot of people really didn't.
If you are interested in DA:3 coming out, there are a lot of reoccurring characters and world themes in these games that get set up in the initial games, but likely won't be required. 3 is a full open world, and is supposed to be a combination of the micro-manage and action RPG of the first two. Interested to see how it works out and feels.