Overall, it's very much "twenty-somethings save the world!" It's not a kids' game, but the characters are all just starting out on their own (either because their family was murdered, because their mother sent them with the group, or because they are on the run and felt that being a nun wasn't their thing after all) -- which gives the group an interesting dynamic.
If you've played the game, you know that you can make choices that affect the outcome of certain scenes. Sometimes the choices are pretty hard (do we kill the boy's mother to save him, or do we spare her and kill the boy?), sometimes they're easy. Your companions have their own outlook on things, and their affection for you will increase when you do the 'right' thing in their eyes. Of course, sometimes make a certain choice will gain approval from one character, and disapproval from another at the same time. That's interesting, but nothing that can be repaired with a private conversation in camp or a well-chose gift.
There is also the chance for romance. Obviously: put a group of twenty-somethings together, put them under a bit of stress, and soon relationships start to form. This aspect amused me the most. There are four companions that you can 'romance', and you get a scene (in underwear) that fades to black when you 'succeed'. I was aiming for Leliana (I dug her accent), but in the end I made a wrong choice in a camp-conversation somewhere and I blew my chances. But next thing I knew, Morrigan was complaining that it was so cold alone in her tent... And Zevran dropped his pants for me when I just so much as pointed at him. :P
Using your choices, you can also choose to play as an 'evil' character. But that doesn't make any sense whatsoever: there's the Darkspawn to defeat, and you need the support of others to accomplish that. Being evil is completely counter-productive for that -- in fact, some of your (human) adversaries are evil, and you can never ally yourself with them. So I allowed my own views to dictate my choices, and mostly I gained the approval of my companions (with the exception of Sten, but I just ignored him).
The bulk of the game is about you building up an army to confront the Blight of the Darkspawn. And all through that process (and in the side-quests) you are pitted against human adversaries, not against the Darkspawn. In fact, the Darkspawn seem like an afterthought to the whole process: only at the start in Ostagar, during your excursions in the Deep Roads of Ozzamar and at the end during the final battle do you directly confront the Darkspawn. But otherwise, you battle the troops of the regent, un-allied monsters or cultists. Or undead, but those are not part of the Darkspawn either.
In fact, I think that the story is inspired by the events of 9/11 and what happened afterwards. The parallels are striking (I think):
Obviously, the Darkspawn are terrorists. The good people of Ferelden (the equivalent of the US) are suddenly attacked, through no fault of their own. It's just what the terrorists 'do', they just can't be reasoned with. And then one of their own (Arl Logain) leaves the king out to die and seizes power for himself -- that's a twisted version of the conspiracy theories the so-called 'truthers' espouse.
And then Logain doesn't seem to care about the Darkspawn at all -- instead, he is paranoid about another nation attacking Ferelden. I see a parallel there with how Bush ordered the invasion of Iraq, even though Iraq had nothing to do with the initial attacks -- he just had a score to settle. The actual terrorists are just an afterthought while Logain seizes power internally -- just like how 'terrorism' has been the reason for the erosion of our civil liberties.
Bhelen says (after you've crowned him king of the Dwarves) that if you're not with him, you're against him (and with the Darkspawn). We've heard that being said many times too. The Dwarves themselves, who confine the Darkspawn in the tunnels of the Deep Roads, are like the soldiers who are stationed in Iraq or Afghanistan. They say things like "you surfacers sleep well, without even knowing that the fact that we risk our lives here is the reason you can do so."
I suspect the obsession Branka has for the Anvil of the Void (an unholy weapon of mass destruction if there ever was one) mirrors the obsession Bush had for finding forbidden weapons in Iraq. That, in turn, set additional bad blood which begat more terrorism -- just like Branka's expedition into the Deep Roads twisted one of her followers into a Broodmother which produced more Darkspawn.
The game was released before Bin Laden was killed. In the game, killing the Archdemon (in the form of a dragon) would disperse the horde of Darkspawn, because they would be without a leader. However, the Darkspawn would start digging for a new Archdemon immediately, just like killing Bin Laden would simply mean someone else could take the leadership. And lo and behold: in the expansion Awakenings, you are confronted with Darkspawn who seem very organised for mindless creatures without a leader....
And while this is going on, the neighbouring countries seem to think that this problem is solely for Ferelden to solve. In fact, some of them take advantage of the situation -- more parallels with the 'we have to do all the hard work'-mood that the Americans sometimes have with respect to their war on terror.
I wasn't very satisfied with the ending: the group disbands, and you're left to your own devices. So I have invested in some downloadable content, namely Awakenings. It's like the third season of Macross: the Big Bad is dead, but now you have to rebuild and face the hurdles of groups of stragglers and unscrupulous humans who try to use the chaos to further their own schemes. So far, I like it a lot.
After I've finished it, I might go for a replay of the whole thing, with a different background. Or maybe just do the different origin stories and see what sticks.