We, too, like to eat at Wine Country Trattoria (TS) in DCA for lunch. (as PP Hound 109 has said) The Pizzeta Salad is really good, and totally sharable between two. (Romaine hearts, Roma tomatoes, smoked bacon, crumbled blue cheese, Kalamata olives with a creamy Italian dressing served on a warm pizzeta crust $9.99) I share this with my DM and get the olives on the side. When I share it with DSis we get no olives, and bleu cheese on the side. The contrast between the warm bread and the cold lettuce is really good. The only complaint I have about WCT is that the breadsticks, while good, should be served warm. They are always served cold. I have even been able to make ADR (PS) at WCT on the same day we go.

I'll stop by the phones outside of Guest Services at the entrance of DCA to call and make them. You can make them with as little as 1 hr. before you want to eat (they can't make them for any shorter time). I love to walk up about an hour after I've made ADRs and only have had to wait a few minutes before we are called. Especially when walk-ups are being quoted 20 min., or so.
Eat outside (if it's a nice day). The patio has a great atmosphere and sometimes you can schedule it for when a parade goes by.
For CS we like Pizza Port. My DD8 loves the Chicken Fusilli at PP and we share it quite often. While Pizza Oom Mow Mow (DCA) has the same pasta, I don't like it as well. Their salads are the same $ as PP but are prepackaged, with dressings in those squeeze on packages.

The salads at PP are mixed and tossed fresh, and are really large. The Chinese Chicken Salad is really good. Also, at PP you can refill your drinks, you can't at POMM.
And don't forget for a quick snack to stop by Mission Tortilla factory to see a (very) short film and get free, fresh, hot tortillas. Flour, or corn, depending on what they are making.
Have a

time!