Ugh, I just stayed down the street from the Opryland last night. There is absolutely north of there except maybe an Applebee's. South of there is Opry Mills (think Gurnee Mills), which has a variety of chain choices, including the Brinker pairing of Chili's and Romano's. It's a long walk, but I suspect that the hotel might have a shuttle.
Wendall Smith's is very good, one of my clients likes to go there for lunch and I was there yesterday. I personally preferred my lunch today at Swett's. But both those places are clear on the other side of Nashville from Opryland.
EDIT: OP, are you going to have a car?? There's a decent burger chain called Backyard Burgers just north of the airport, which is within a 15 minute drive. And there's a Waffle House if you're into that (I like a cheap waffle for dinner sometimes) across the highway from the Gaylord.
"Fried chicken should unify us, as opposed to tearing us apart. " - Bomani Jones