Dallas to Yellowstone- best non mountainous route

we like the rock springs, wy, to pinedale, wy, hoback junction, then up to Jackson, Tetons and into yellowstone from the south. Jackson will have some white water rafting on the Snake River, and a ski lift and a shootout on the square every afternoon.
Yellowstone will have horse back riding, wagon ride, hiking, boat excursions on the lake.
wi fi will be iffy in the parks, but available around the lodges and visitor centers and up by Mt. Washburn. Take binoculars.