My husband and I are coming to Washington DC at the end of March for a business event/formal dinner. We will have all day Friday for sight seeing and eating out. I haven't been to DC in about 20 years but remember having fabulous meals. I'm interested in recommendations for lunch and dinner - doesn't have to be very fancy, but we love great food. We'll be staying at the Renaissance Arlington and won't have a car, but we'll be happy to take mass transit to get around. Thank you Chowhounders.