Hello fellow Tennessean, Carrie! My family and I have attended Night of Joy, and we loved it! There is something so special about this event! It packs many favorite artists into one big celebration! While not all of the ride attractions in Walt Disney World are open, the ones that you have mentioned specifically have historically been open. Attractions that are typically not operating during this event include Walt Disney World Railroad, Liberty Square Riverboat, Walt Disney's Enchanted Tiki Room, Jungle Cruise, Tom Sawyer Island, The Hall of Presidents,and Monsters, Inc. Laugh Floor. Of course this is subject to change, but this is what has happened in the past.
Here's another perk you may want to know about for your trip. If you purchase Night of Joy tickets for BOTH nights ON OR BEFORE August 11, 2015, you will also receive one admission to Disney's Blizzard Beach, Disney's Typhoon Lagoon, OR DisneyQuest Indoor Interactive Theme Park. The admission to one of those is valid from September 8 – September 14, 2015. (Fine print: Water Parks subject to rehabilitation, seasonal and weather closures.) Happy planning and have a Magical vacation!