If it's OK with you, I'll tell you the highlights for us.
Flew into Denver, 1st night Boulder, then out early in the morning. Drove through Medicine Bow National Forest and stayed at Centennial. We would have taken in Estes Park, but were too early in the year and it was snowblocked.
3rd night, Pinedale (south west of Riverton). We drove via Rawlins which, if you do go by, has an old prison that is interesting to visit.
The drive into Grand Tetons NP is beautiful from theron.
Jackson Hole is a dull tourist trap.
We had one night in Grand Tetons (which is enough).
Then 3 nights in West Yellowstone, spending our time travelling round the park.
I by far preferred the areas outside of the park. Once you've seen one buffalo, you've seen them all. Especially as they're surrounded by crowds of tourists taking photos. Ditto geysers.
[at this point we made a detour up into Montana, but I can't remember the itinerary. However, we stayed in Bozeman, a very pleasant university town, and a night in Martinsdale, north on Highway 89, and then the 294. Martinsdale is tiny, and has a great little hotel. From there, you can visit Castle Ghost Town, one of the many abandoned ghost towns in the area. We also visited Helena, of which, the least said the better.]
I loved the drive from Tower Junction, on the NE corner of the park, to Red Lodge via Bear Tooth Pass. Just wonderful. and not blocked with other tourists.
Red Lodge is a good place to stay, with an old-fashioned cinema.
We then stayed at Cody. Nowhere special, but a good museum.
Then - another favourite - Thermopolis. A green oasis with hot thermal springs. One of which is free for the public to use.. Also, an area of ancient petroglyphs nearby, which are fascinating (especially if you get a guided tour).
Then south. We stopped at Steamboat Springs - a useful stop, nothing more). But then south to Leadville. One of my favourites. An old prospecting town. Really interesting. You can hire pushbikes and do a day cycling round the old mine workings (which is a hell of a lot more fun than you'd think).
Then back to Denver (nothing special)
To be frank, the towns are not what USA holidays are about for me, but I love the landscape, and the people. Try and stay in at least one B and B. You usually sit round and have breakfast with the other guests and host. That sounds terrible, but we always had an interesting meal.
In short, the highlights for me were the drive to Red Lodge (in fact, most of the driving), Thermopolis and Leadville.
Have a great time!