We were exceptionally happy with the West Yellowstone KOA. We had a premium site with patio, large new concrete table and bench, adult swing, shade trees, and really level. The indoor pool, family activities, and location were great also. In Jackson we stayed at the Virginian. It is a nice gravel RV park behind the Virginian Hotel/motel. Guests have access to all hotel amenities (pool, laundry). Very friendly, clean, and a great central location only about a mile from central Jackson. While up there if you need service or rentals I highly recommend Big Sky. We needed RV service during our trip and they were fantastic, making us mobile in the evening so we could return to the campsite, and finishing up when the parts came in the next day. We also rented a 15 passenger van from them so our entire group could tour together.
Happy Trails.