Get up to a $750 Disney Gift Card FREE when you buy a 5-night/6-day non-discounted Magic Your Way package at select Disney Resort Hotels!
Eat, play and shop with the Disney Gift Card. Use the card to cover vacation expenses: dining at your choice of Walt Disney World® restaurants, special event tickets, sports, recreation, tours and moreall this in addition to shopping! With your gift card in hand, the world is yours!
The above is taken directly from WDW website. I think it's safe to say that if it's included on the dining plan, you can likely also use the GC there. There are some restaurants, particularly at DTD that do not accept the dining plan and are not owned by Disney. If you have a question about a specific restaurant, you may want to call that restaurant directly.