Looking for rec's: D.C. and Paris

[splatgirl]

So I'm off to Paris on Tuesday with a two night pause in DC to see the Julia Child kitchen at the Smithsonian which I have been wanting to do since it first got there.
Looking for recommendations on WFO pizza places. I have a lunch and a dinner open in D.C. and am not at all adverse to two pizza-centric meals, or second lunch or late pizza breakfast. I know you guys know the real thing vs. the sorry imposters, so lemme have em.
I'm already semi-committed to Radius for one of those meals only because the pizzas have motorcycle names which I love (and it will be a fun surprise for Boy) but Pizzeria Paradiso seems to be well-reviewed, too. Thoughts? Something better? What to order?

And then Paris. France, not Texas. And yea, I'm going to eat croissants and baguette and cheese and macarons until my eyes pop out of my head, but if there's a fun and good WFO place, I'm 100% in. And bread. Of course I will do the requisite Polaine visit (should I consider bringing home a miche to enjoy the week of my return? The thought of Boy's reaction to me spending that much on bread makes me laugh) and I'm definitely going to check out Eric Kayser, but what else?
Anything else I need to know that I might not have already read about in the realm of food in Paris? This is my first visit. We are renting an apartment so cooking, Oui!
Holy cow am I excited!