The most notable attraction outside of the Disney World theme park is Downtown Disney. Although the area is open during the day, it really comes to life in the evening. With lots of shops with Disney merchandise, other companies are present as well, such as the Ghirardelli chocolate company.
Entertainers roam the street, creative a festive, free for all mood typical of a great party. Area restaurants such as the Fulton's Crab house, provide a scenic and excellent dining experience. The large offerings of steaks and seafood cater to all tastes. I probably ate the best lobster tails there!
Downtown Disney is basically three different interconnected areas: The Marketplace is where shops, restaurants are all next to each other. The activity and crowds grow as the evening progresses.
Pleasure Island is, as the name implies, a fun place where nightclubs and theaters are located. This is a place where the main activities start at 7 pm and continue for about 7 hours, until about 2 am. Notable attractions are the Comedy Warehouse, Motion (a dance venue), the Adventurers Club, BET Soundstage Club and other various establishment such as Raglan Road Irish Pub & Restaurant.
In the same area there is also an AMC Theater Movie Megaplex, just in case you are in the mood for a movie.