Dragon Age: Origins, is a very traditional RPG. I've said this before, but I can't stress it enough. The gameplay is nothing like anything I've played in years. It reminds me most of Neverwinter Nights 2, which is a really long (like recent Final Fantasy games long) RPG based on Dungeons and Dragons' Forgotten Realms.
The subtitle of the game comes from the 6 Origins stories that you choose from at the beginning of the game, with limitations from race and class. These are short (relatively, anyway. They're a couple hours long) introductions to the world and your character, and they all converge into the actual game when you are inducted into the Grey Wardens, an order devoted to defeating the evil Darkspawn, blah blah blah.
The basics of the plot may sound very cliched and boring, but it's the writing and the details that make the game what it is. This is where the developer, Bioware (best known, now, for the Mass Effect series), shines.
The game is laid out like pretty much every Bioware game I've played: introduction area, several middle areas that you can choose to do in whatever order you wish, and then the (epic) finale.
These middle areas are the meat of the game, and unlike in even other Bioware games, feel very diverse, which is a very important thing in a game as huge as this one. You do everything from saving a town from a zombie invasion, deciding the result of a civil war, to finding a sacred relic to heal someone. These quests all feel very different, and that's a combination of several different aspects, including the writing (phenomenal, as always), art, and level design (I especially liked the part finding the sacred artifact).
The biggest problem I have with the story is sometimes it's a bit too traditional. There's a part in a forest where I'm talking to this giant talking tree that's decidedly reminiscent of Treebeard, and just a few minutes later I'm falling asleep next to a river. (Go read Fellowship of the Ring, if that didn't make sense) That's a minor flaw though, and almost unavoidable in a game as huge as Dragon Age is.
There's also TONS of sidequests. A lot of them don't really have much story, as in get them from a quest board, go do them, and turn them in, but some of them are pretty good. Of course, there's the obligatory companion quests, which are awesome as always, if not as good as Mass Effect 2's. (which are the high point of that game, so they shouldn't be.)
Overall, the story is the main draw of the game, and definitely lives up to Bioware's ridiculously high standards.
This is where the game got a bit iffy for me. It works pretty well, but it's immensely complicated, and if you're not very good at strategy, it will be quite hard. For some reason, there was a really big jump in difficulty, so big that easy is pretty much just going from room to room killing everything, and Normal is a complicated test of strategy. I'm not sure if I'd like to see the guy that could beat Nightmare difficulty or not...
Anyways, there's three classes and three races, and they're so cliched you can probably guess them without me telling you, but I will anyway. You can be a Human, Dwarf, or Elf, Warrior, Rogue, or Mage. What makes this work is that each class has around four different tacks you can take. Each class has several different talent (or spells, for Mages) trees. For example, the Warrior has the main warrior talent tree, and then the Weapon and Shield, Two-Handed, Dual Weapon, and Archery trees.
Each class also has four different "specializations" they can learn, further customizing the character. For the Warrior, these are Templar (mage-hunters/paladins), Champion, Reaver, and Berserker.
These work really well in customizing your character, and even though you get nearly a dozen characters in your party, they end up being very unique and different in their playstyle, let alone the way they act.
I think my problems with the gameplay are just that, my problems, and it just depends whether you will enjoy it or not. It's made and balanced really well, so it just depends on you whether it's the kind of thing you like to do, and if it isn't you can always just turn the difficulty to easy.
Visuals and Sound
Nothing too specific here. Good soundtrack, nice and epic, very reminiscent of classic fantasy movies and the like. The combat sounds awesome, and the voice acting is incredible, as always, though I wonder why they give other nations real-world accents. (seriously, there's a nation that sounds French, and one that I'm pretty sure is Spanish.) Ironically, my biggest problem with the sound is that I can never find a player character voice that I actually like when it gives you the choice. It would be the lack of your character talking, but I accept the fact that it's just impossible to have the PC (player character) talk in a game as huge as this with as much diversity possible.
The visuals aren't the best in the world, but it still looks awesome when you take down one of the big boss monsters, especially something like the High Dragons. (I can post some pictures, if you want.) There's blood and gore everywhere during the fights, and occasionally you'll do something fancy like slice their head off, and the weapons and armor look suitably epic.
Just bear in mind that this is probably the most traditional RPG you will ever play, and you'll be fine, as it's also probably the best RPG of this kind you'll ever play. It does have some issues, but these pale in comparison to the sheer experience you'll have if you enjoy RPGs.