The actual city of DC is nice if you stick to the capital area and surrounding nice parts. There are also really *not nice* areas in DC, it's like most major cities so it has it's pros and cons. The big cons of DC being traffic (worst I've ever seen in any major US city) and crime if you wind up in the wrong areas. But DC has some very nice culture, especially in the food scene which would be great for your wife.
I've never lived in NC but I have friends living in the western part of NC and also in the Raleigh / Durham area and they all really like it. I think Jorge on the forum lives in NC so he can speak more to that.
Obviously NYC is the penultimate in food when it comes to the US, but that's a major lifestyle change from anywhere out west.
I can't really speak to living anywhere north of the DC metro area because I haven't done so since I was a kid, so that experience doesn't really count (NYC area, Staten Island outside the city).
My stay in Reno was just for a weekend, so we only saw the touristy stuff. I was there because I was doing an internship at Lawrence Livermore National Labs in CA during a summer while in college, and we took a trip to Reno for a long weekend, so I really have no idea what living in that area would be like.
