These are 2 very different places. Boardwalk, is a Disney resort with a real boardwalk. You can walk there from the IG at Epcot. It has many resturants, shops and entertianment (including ESPN zone0. During the day it is pretty calm and you can rent surrey bikes, at night it turns into a real boaardwlak, games, entertainment etc.
DTD is very large. It has everything from shopping (World of Disney,
Lego, Once Upon a Toy) to restuarants (Wolf Gang Puck, Planet Hollywood, Rain Forest Cafe, etc.) to movie theaters, Pleasure Island (evening comedy clubs) and Cirque De Sol. On top of that you also have Disney Quest, electronic games, simulators and cool teen place,
There is lots to do and enjoy
Sandy