DC is fine. But "DC" is a tiny part of the "DC area". I grew up in Annandale. A car was necessary. An old friend of mine lives in Alexandria, in Del Ray. He takes the train into DC (which takes him about an hour total, when you add up the walking, waiting and riding). But his family needs a car because his wife works in a school that is not in walking distance, their parents live in Arlington and northwest DC, and most of their kids' activities require driving.

In DC, as in San Francisco, the trains are more for commuters to get into and out of the city. They're not really for connecting within or outside of the city. The NY area is better about that. (But not great.)

If I ever moved back to the area, I would seriously consider Bethesda. Easy access to DC, and a neat town in its own right.