Grand Teton Park, Moran, WY

AuntEthel, unless you are worried about an hour trip each way from Colter Bay to the entrance to Yellowstone with some very nice scenery, you could stay in Colter Bay and day-trip to Yellowstone. We do it all the time, even towing our boat from Colter Bay to Yellowstone Lake to fish for the day. A person can leave pretty early in the morning to miss car traffic and tour the parks loops, one per day, and get back a little late in the evening, just in time to watch the beautiful sunsets on Jackson Lake as you are having dinner, etc.