For your situation, I would recommend the Residence Inn Dupont Circle. Only a Cat 6 (versus 7+ for the rest of the city). You'll get the free breakfast, plus it's only 2 blocks to the Dupont Circle metro. While there aren't too many cultural attractions in the immediate area, this neighborhood is very nice and safe and has a ton of great food and drink options. You will only be 2-3 metro stops away from the downtown DC attractions and a quick uber/bus right to Georgetown. Also easy to get to Pentagon City later - just go 3 stops to Gallery Place, and transfer to the Yellow Line for a few stops. I think it's your best bet.