We just came back from a one week trip to DC. The first half was business - we stayed at the Gaylord National Harbor hotel - brand new but expensive and in a developing neighborhood. My kids loved it though...we had a balcony that faced the atrium and at night there was a water feature with lights and music - not unlike at Epcot, but on a smaller scale.
Then for the second half we stayed at the Omni Shoreham, about 4 blocks from the National Zoo. I snagged a travelzoo rate of $109 a night but once you add the valet parking fee of $28 and resort fee of $15, its closer to $150. I wanted to love the Omni Shoreham but found it just okay - I don't mind that it was built in 1930, I like hotels with history, but I did mind the heavy banging doors all hours of the day and night. Its in a nice neighborhood with some great ethnic restaurants and about a block to the Metro station. My husband objected to the staff at the hotel that always seemed to have their hand out for a tip.