I'm not familiar with the tour groups because we always drive it ourself. I will say that I have been at a number of areas where a tour group shows up, everybody piles out of the van or bus, quickly take their pictures, and move on. They have a schedule to keep and unfortunately not everyone has the same interests so you may get pushed along when you'd rather spend some time at a given place and you may get bored if they see something that doesn't appeal to you. Another option would be to rent a car in West Yellowstone and see what you want, when you want. Driving really isn't bad in Yellowstone and I'd rather run my own schedule and eat and rest up wherever and whenever I choose. Anyway, that's another option you may want to consider.
Here's A Link to a couple of places that rent cars should you decide to go that way.
We always stay in Grizzly RV Park when in West Yellowstone. It's one of the best parks around and is the closest thing to the downtown West Yellowstone area and is easily within walking range. It was a good park 12 years ago and it is getting even better every year.
Nearby Grizzly RV, you can walk 1/4 mile east to the Grizzly and Wolf Discovery Center. Also, the large Imax theatre is right next door to it. If you walk 2 blocks north you are right on the main drag, Yellowstone Avenue, one more block north is Madison Avenue. Right on Madison Avenue is Wild West Pizza, which is very good pizza and they will deliver to Grizzly RV if you want. Also on Madison is Bullwinkles, which has excellent food for dinner. Really top shelf stuff, a tad pricey if you order stuff like the Elk medallions but they stuff you with huge proportions and it's all really good. We bring doggie bags back to the RV (okay - people bags
). The Timberline Cafe is found on Yellowstone Avenue. This is a great place for breakfast or lunch. They have home baked pies, good soup, burgers, sandwiches, and plate lunches. We haven't eaten dinner there though because we either have pizza, cook in the RV, or go to Bullwinkles. Plus, they are 2 blocks from Grizzly RV. All of the shops are right in the same area so it won't be too far to lug all that stuff back to the RV. Then again, it won't be so bad because after buying all that stuff, you're wallet will be lighter.
Also, when you do enter the park at the West Entrance be sure to use the far right lane when passing through the ticket booths. You wouldn't believe how tight the other ones are and you might fold up a mirror going through. Don't ask me how I know that.