I was just in DC for the first time last weekend and thought Pizzeria Paradiso in Dupont Circle was, all things considered, pretty tasty. I don't think it's as good as Via Tribunali here in Seattle, but I certainly enjoyed it.
Back on topic, I found DC area to be not particularly geared towards startups. There is a lot of IT/software business in the area, but it's overwhelmingly about government contracts. It's not like SF or Seattle where real products and companies are getting invented, built, funded, etc every day.
While DC is an interesting place to live for a short while, I can't really recommend it as a destination. The traffic is horrendous. The climate is weird (how a place can be so sticky and humid in summer, and so bone-chillingly cold in winter, I'll never know). The culture is not especially geared towards entrepreneurial types. And it's expensive.