My mother in law is in town for the weekend and wants to take us to dinner tonight somewhere in DC (the city, not surrounding areas). Although she said she'd take us anywhere, it needs to satisfy her tastes first and foremost.
So base your recommendations on the following:
Dinner somewhere in DC ($$-$$$)
-American or Italian
-safe, slightly upscale to upscale
Think of Buck's Fishing and Camping as a starting point.