DAO is fairly typical for a Bioware rpg. If you've liked most of them, chances are it will entertain you to some degree at least. The world is fairly well crafted, the companions fair, the plotline decent (if not very original) and as a whole knitted together quite well. It's not a work of art by any stretch of imagination, but it's a quite well made game.
The mechanics suffer a bit from artifacts from older games, so depending on how high tolerance you have for such systems that can alter your perceptions. The origins themselves were fresh and interesting, but not nearly as well utilised as they could have been sadly.

DA2 is bolder, but suffers a lot from execution. It's the first time in a long time Bioware moved away from their "standard plot model". It's still unmistakingly a bioware game, and if that is not your cup of tea then I doubt the plot will excite you much. The protagoniost is much less of a blank slate though, which has the benefit of actually being able to interact with the plot but may result in a percieved loss of agency.
The mechanics are largely the same, but with a few crucial changes to creation, encounters and pacing. It's much faster than DAO.
The companions are quirky and provides less setting exposition than in DAO, but are very involved in the plotlines and have their own story-archs through their multiple companion quests.
Sadly, the game suffers a lot from a short development cycle and perhaps from a poor decision or two. The DLC adventures shows significant improvement in these regards, but if you didn't like the original then it's no point in acquring them.

A key difference is that DAO is fundamentally an epic, it's about heroics and adventuring and in the end of the day triumphing but perhaps with a bittersweet note.
DA2 is not. It's more of a drama or a tragedy.It's not about adventures, it's not about saving the world. It's about you and being dragged along in a series of events.

I personally liked DA2 more than DAO (but I love that game too), but that's neither here nor there.