Don't know much about Appleton dining, but Tom's Drive-In is a small fast food chain that is pretty good. The Paper Valley Hotel has a steak house named for Vince Lombardi, but I don't know how it is, except probably overpriced. But if you are willing to take a rather boring 20 mile trip down the road, Ardy & Ed's Drive-In in Oshkosh is a terrific little place that has been there since 1948. It is full-bore old fashioned, with 50's music and carhops on roller skates, and GOOD food. Al Roker featured them in Roker On The Road.
Everything they have is good, but I particularly love their ho-made barbecue, which is not any kind of barbecue, but just one more name that we have here for sloppy joes. This sandwich is everything a midwest sloppy joe should be -- big and meaty, with the golden juice soaked perfectly into the soft, steamed bun. My standard order was two barbecues, fries with tartar, and a large beer. Living in La Crosse, I sure miss them. We do have such a drive-in here, but they don't have that sandwich.
And you get a nice view of Lake Winnebago while you dine. This is where they have the big sturgeon spearing contest each winter.
Oshkosh has a big "discount" mall too, but you can skip it. Mostly it's all factory stores, and the prices are no cheaper, sometimes higher, than the department stores. http://www.foodspot.com/ardyandeds/
They are closed now for the summer, but right near by on Doty Street is Hughes Chocolates, a family operation that makes and sells the chocolates out of their shop in the basement. This is beautiful stuff, good prices and clean as a whistle. They are always busy, but at Christmas time the line can stretch from the counter in the basement up the stairs, out the door, and down the driveway to the street. There is just a little sign stating their name in the front window, but everybody knows where they are.