Allison,
If you go with a Moderate, I would recommend
Port Orleans French Quarter. You can take the boat to Downtown Disney, giving you access to the nightlife that includes Raglan Road, Bongos, and House of Blues.
If you go with a Deluxe, I would stay at either the
Yacht Club,
Beach Club, or the
Boardwalk Inn. These put the Boardwalk outside your door with the nightlife of Jellyrolls, the ESPN Club, and the bars and restaurants at the Swan and Dolphin. Just as importantly you can go, if you have a park hopper, into the Epcot World Showcase.
I would prefer the second choice, though it is more expensive. I love to walk the World Showcase and try the different drinks and appetizers at all the national pavilions. I also love to do a bit of worldly window shopping along the way.
Before the closing of Pleasure Island, I might have told you to go with the Moderate. Now, I would definitely say that if you can afford the Deluxe, do it. You have a great evening escape just outside your door, with a seemingly endless supply of places to explore and discover.
Have a great vacation!