Calling all fashionistas!
So it dawned on me today that I don't have any "nice" dresses. Like, I have cute dresses and dresses I wear out, but for Fi's birthday (in April) he is taking me on his annual Napa birthday trip (where he likes to eat at one of the Michelin started restaurants). I figure it'd be good to have a dress in case we go to nice places. Maybe 1 short and 1 long? I have NO idea what's I be acceptable, and these are my ideas:
http://m.nordstrom.com/Product/Details/3703020?origin=browsehttp://m.nordstrom.com/Product/Details/3709064?origin=browseProbably not those EXACT styles, but am I at least on the right track?
This is the only time in my life I haven't been able to dress myself. I have NO experience with going to exceptionally classy places or formal events.

Ideas and help please!