Covering 3, 471 square miles, Yellowstone National Park is larger than the states of Delaware and Rhode Island. Because it is so large, all places to stay are equally inconvenient. You will find a lot of bad information on the www about where to stay because the purveyors of lodging do not want to discourage you by pointing out how long it will take you to get to what you want to see in Yellowstone National Park. The first web site I came across pushes staying in Jackson, WY. Its about 100 miles from Jackson to Old Faithful. Goggle Maps also gets it wrong. Goggle Maps says that 100 miles takes 2 hrs. and 15 min. We do not go to Yellowstone National Park in season, when most people go and the roads are most crowded. On one shoulder season trip in October, it took 45 just to go 10 blocks through the center of town, and I know the fast alternatives. You have to do this for most Jackson motels. The 100 miles starts after the 45 minutes, and you will not come close to averaging 50 mph, even in light traffic. Unless you change your lodging locations, you will always be along way from most of Yellowstone National Park.
Because we have done a dozen or more visits to Yellowstone National Park over the last 22 years, we don't try to see the whole thing unless we are taking first time visitors on a tour. Our main target is Yellowstone Falls, so it logically follows (see discussion below) that we prefer to stay in Cody, WY. There may be a lesson here for you-- do your planning. Lay out your top choices, and stay near them. If you want to see 'everything', location pretty much does not matter. All places to stay are equally inconvenient.
Places to stay fall into one of two categories, and I exclude camp grounds and RV parks;
1] Inside the park
2] Outside the park
Compared to most National Parks, Yellowstone National Park has a lot of inside the park lodging: Grant Village, Canyon, Mammoth, Old Faithful. There are three hotels at Old Faithful, and the whole Old Faithful complex is so big that its like you never left New York City, with more parking lot than Nature.
Canyon is a smaller complex and the closest to the Grand Canyon of the Yellowstone, our favorite place in the park.
The old hotel at Mammoth is isolated from the rest of the park.
If I were to stay inside the park, I would stay at Grant Village because its pretty isolated with a nice setting on the shore of Yellowstone National Park's largest lake, and right next door to a small but active geyser basin.
We have never stayed inside the park because there is no advantage to it. All places to stay are equally inconvenient, be they inside or outside the park. The hotels inside the park are old and “historic”. We have had our fill of “historic” hotels inside National Parks. They don't meet modern comfort standards, and 3 or 4 was enough. Since we did that before we got to Yellowstone National Park, the park hotels have no appeal. Inside park lodging is also expensive. Always. And rarely worth it except for historic value.
South Entrance: 1] There is one motel between Yellowstone National Park and Grand Teton National Park. I think you need to make reservations a year in advance. We tried to get a drop in room three times with no luck; 2] Grand Teton National Park, but if you are going to pay inside park prices, why not stay in Yellowstone National Park? 3] Jackson, WY-- too far away. See above discussion.
West Entrance (town of West Yellowstone). Excepting far away Jackson, WY, West Yellowstone has more beds for rent than any of the other captions. Look at a map of Yellowstone National Park's Great Loop Road, and you will see why. We have stayed in West Yellowstone twice, and don't like it (we never would have gone the second time had not my sister come up with a free stay at a luxury condo hotel). Theoretically, West Yellowstone is a town, but, in reality, it is nothing but over priced motels, over priced mediocre restaurants, over priced souvenir shops, over priced gas stations, and an over priced grocery store, and homes for the staff of them. .
North entrance-- Gardiner, MT. -- a very small town. I don't remember the first place except that it overlooked the river and was OK we stayed in Gardiner, but our next three stays were at the better than average Comfort Inn, 6 miles from Mammoth hot Springs.
NE entrance: A tiny town with limited choices. We have never stayed there.
East entrance: Cody, WY. Our top pick because it is closest to our favorite place in Yellowstone National Park, has lower prices than most of the other possibilities, has local diversions, has our motel (see Tip on Cody Roadway Inn) and good food. Although its almost an hour drive from Cody to Yellowstone National Park, its a scenic road. The longer Chief Joseph Scenic highway is even more scenic.
The Yellowstone National Park web site says 7 hours is enough for a short visit to all the major sights which are along the Loop Road. I'd take two days as the minimum, figuring no hiking. If you are driving, you will have trouble finding a parking place at some stops. Late last October, it took us 3 or 4 tries to find an empty parking spot at the Grand Prismatic Spring.
A lot of tourists heading to Yellowstone fly into Salt Lake City, but an SLC rt flight will "cost" you two days of time on the road for going to Yellowstone and back. Bozeman, MT, on the other hand, is less than a two hours drive from Yellowstone's west or north entrances. Billings is a little further away, but if you are renting a car, you get to go over the spectacular Beartooth Highway from Billings (via Red Lodge) to get to Yellowstone. Idaho Falls is also worth a look because it lends itself to nice loop drive-- airport to West Yellowstone to Grand Teton National Park to Jackson, WY, over the Teton Pass, and back to Idaho Falls.
The Bridge and River tour is a scenic 3-hour bicycle tour will take you from the Upper West Side of New York City up and over the George Washington Bridge for a ride along the river on Route 9W. Get the full touring experience and leave New York City for a few hours. During the ride, we make stops at Grants Tomb Memorial on the Upper West Side.