There are multiple departures from Boston to Washington starting at 5 in the morning up until 10 at night. Regional trains offer Coach Class and Business Class and the trip takes about 8 hours. Acela Express trains offer Business Class and First Class and total trip time is about 6 1/2 hours with a top speed of 150 mph. The Federal is an overnight train which departs Boston at 10pm and arrives in DC at 7:30 the next morning. This train offers Coach Class, Business Class, and First Class Sleeping Car accomadations. All trains have a Cafe in where passengers can purchase a variety of drinks, snacks, and light meals. Business Class passengers on the Regional trains receive complementary non-alcoholic drinks and First Class passengers on the Acela Express have a presonal car attendant who will serve complementary drinks, full course meals, snacks. Sleeping Car passengers on the Federal receive free items from the Cafe car, personal attendant who will help you with your luggage and convert your room into day/night accomadations, and a shower is located at one end of the car.
Regional Coach Class has 74 seats per car, two on either side of the isle, with restrooms at one end, and overhead luggage racks.
Regional Business Class has 60 seats per car, two on either side of the isle, with restrooms at one end, foot rests, rail phone, and overhead luggage racks.
Acela Express Business Class has 70 seats per car, two on either side of the isle, with restrooms at one end, foot rests, rail phone, and enclosed luggage bins.
Acela Exprees First Class has 44 seats per car, in a 2-1 configuration, restrooms at one end, foot rests, rail phone, and eclosed luggage bins
Federal Coach Class - see Regional
Federal Business Class has 45 seats per car in a 2-1 configuration, restrooms at one end, foot rests, calf/leg rests, and overhead luggage storage.
Federal Sleeping Car is of a Viewliner type. Two levels of windows in every room. Standard rooms have two facing seats which convert into a bed at night and another bed drops down from the ceiling. Each room as a toilet and sink. Deluxe Bedrooms have a large sofa that converts into a wide bed at night and another bed folds out from the wall, there is also an inclosed toilet/shower, and a vanity.
I'm sure others can add on to this and make changes.