I visited Washington DC for business and stayed at the Renaissance. The company paid $200 per night.
If you are arriving at Reagan National Airport and you do not have much luggage, head straight on to the Metro station (subway) and catch the Yellow line (to Fort Totten). The subway will take you straight downtown. exit at the Chinatown/Galleria stop and you can resurface on 9th street. the hotel is a couple of blocks north on 9th and H st. (numbered st going N-S and lettered st going E-W) If you travel outside of rush hours, it's $1.35 for the trip.
On weekdays, the place is primarily for business travelers. I didn't see much in terms of families with small children. so it's quiet. the swimming pool is under renovation (during my stay around 6/08) Typical business hotel as seen in neon lights 9instead of incandescent) in the bathroom. the room is clean and a copy of USA Today is delivered every morning. there weren't really any features that make it distinct (like Embassy Suites layout and full breakfast)
Bring a good pair of walking shoe if you like to explore on foot. I saw a lot of kids with flip flops; those are not very comfortable for long walks. Some good chain restaurants nearby (Ruth's Steakhouse, McCormick and Schmick, Starbucks for your caffein fix, etc.) or you can walk to the Amtrak Union Station by the US Capitol and try B. Smith restaurant (if you prefer a non-chain restaurant) inside the station there are lots of fast food places.











