I'm attending a party at a fancier restaurant where the host said that the dress should be "smart casual". I've talked to a few other girls, who go out to occasions like this more frequently than I do and they are planning on wearing cocktail dresses, which I know they have a large selection of. I'm incredibly poor right now, so I'm attempting to make an outfit out of what I have at home! I'll be throwing a black shrug and tights under this (I'll be travelling by transit in about -13F weather, brr) and wearing black pumps (carrying them with me, wearing fairly classy black knee-high boots for travelling): http://www.polyvore.com/cgi/img-thing?.out=jpg&size=l&tid=11592029

Is this dress appropriate? My only other options are a silky blue dress of a similar cut, and a navy sheath dress that I usually wear to interviews; as well as a few casual dresses.