There's a lot of good pitstops along the way. In the Hyattsville area, I recommend Shortcake Bakery, which is on the NW Branch trail at Route 1. A little farther up Route 1, and easily accessible from the trails via neighborhood streets are Franklins (brew pub/restaurant), Busboys and Poets, a Yes Organic market, and a bunch of other restaurants.
Farther up, along the College Park trolley trail/Rhode Island Ave. area are REI and Proteus bike shop (where my wife works). Proteus is having their annual sale this weekend, and Jill and Yo are down from NY and helping work the sale, so drop by and say Hi!
My favorite restaurant in the area is Fishnet Restaurant, which is right on the trolley trail in Berwyn Heights. In the REI shopping center, there's a MOM organic market with a nice bakery for ride fuel.
Even further north, I recommend visiting Old Greenbelt before or after a good hammerfest in the Beltsville farms. The New Deal cafe has good Lebanese food and often has excellent live music. And sometimes belly dancers. There's a COOP grocery store, a Chinese restaurant, and lots of nice outdoor seating for that re-fueling stopover.
The Greenbelt metro station is a great central location for local rides. Good bike lanes make it easy to cross the beltway on Cherrywood Lane or Rhode Island Ave to get access to the Beltsville farms and Old Greenbelt. Go through the Metro tunnel to get to the REI/Proteus/Rhode Island Ave. side.
One warning: I don't recommend casual riding on Route 1, Route 201 south of Cherrywood Lane, or on Greenbelt Road (Route 193) at any time -- just too much fast traffic for me to be comfortable. Fortunately, with a little experimentation, there are lots of great side roads and trails to get around.
Happy riding this weekend! Weather looks perfect today and Sunday, but maybe a bit windy on Saturday. -Jeff
Definitely a great day to stop by Proteus! I was going to ride in this morning, but woke up with a headache.... ok, that's a lame excuse, usually a good ride will clear up a headache. I was just kind of tired and lazy and didn't feel like getting up to ride. I was going to bike by Proteus on the way home, since that sale is kind of crazy, but I'll just have to drive by instead!