Yellowstone is a wonderful place. The thermal features, the animals, the lake, the mountains. Start a "Yellowstone fund." Put some money aside each week. If you RV it, from Indiana it will take about 4 or 5 days to get out there. If you fly into Jackson, you can spend more of your vaction time there. I would suggest to stay in the Canyon area of Yellowstone, it is more towards the center of the park and gives you easier access to the rest of the park.