Planning a trip from NYC to Yellowstone. So far, reservations for 5 nights at Grant Village motel, hi end room, from 7-25 on.
Is that an ok location? Ok time to go? Is 5 nights about right? Will fly in to Salt lake city, need hotel close to airport, too. Any particular route/sights en route to Yellowstone? Car rental advice? Thanks so much!

Lets see...Grant Village in the Park is Ok..as is the Lake Lodge, Old Faithful, and Canyon Inn..If you have 5 nights of confirmed reservations at Grant Village..keep them and stay there..as you will probably not find a room to be had at any other the others..Also, it is the weekend for the annual 24th of July Holiday for the entire state of Utah and alot of Utah folks head to Jackson and Yellowstone during this week..which only adds more pressure to hotel reservations..so I would absolutely recommend that you keep your 5 night of reservations at Grant Village..It will be a good base camp for seeing the Park ..and you can return there each night and not have to unpack...It is a OK location absolutely. and as far as 5 nights..there is plenty to do to use up that much time easily....although since I have been to Yellowstone dozens of times over dozens of years, 5 days is a bit much for me..
Any particular sites...well I assume you are driving thru Jackson and the Tetons..actually there are various routes to take to get to Yellowstone from SLC ..all are quite scenic..some more than others...and roads are good...some better than others..
The car rental agencies @ the SLC airport is about as convenient as any car rental place I can think of..just walk out side of the baggage claim area in Terminal 2...and walk across the pedestrian walk to the car rental building...it is all of about 100 feet..all of the car rental agencies are located here..If you need any further specifics...please feel free to let me know ..have a nice trip !!

I am doing the same type of trip in late May. I am staying at the Fairfield Inn near the airport. My travel agent got me a good deal with National.

You have my sympathy if you are at Grant Village. It is ok as motels go, but it contributes nothing to the character of your visit in the oldest of our National Parks. I think 5 nights will enable you to see Yellowstone and drive down to the Tetons. They are well worth the trip.

In Yellowstone, I have two geysers that I dearly love to watch: Grand and Castle.

If you want a lovely walk along a flat trail, take the walk to Lone Star Geyser. I plan on doing it again this year. We take along a picnic lunch and snooze under the trees until the geyser erupts.
The trail follows the upper Firehole River through an unburned section of the park. The forest vistas are beautiful and the walk is relatively tranquil.

Other than that, I enjoy the walk between the Falls of the Yellowstone River and Artist's Point.

.....opps...regarding hotels near the airport..first...the airport is only a bit more than 5..but less than 10 minute drive into downtown SLC ..where there are several hotels of all price ranges...also as well there are numerous hotels located near the airport....you will not have a problem....

I forgot about the Tetons.
If you want a good view of the whole range, take the narrow road up Signal Mountain. It is actually a laterial moraine made up of till left by the retreating glaciers. You cannot really tell it because trees and other vegetation cover it.
There is a view point near the end of the road that I think you will enjoy. If you want to take pictures, I suggest that you bracket the exposure if you have that type of control over your camera.
I have tried several times to get a good picture from Signal Mountain, and my most successful shots resulted when I took three exposures.
The first exposure was right on the light meter setting, the next one was 1 F stop up and the third one 1 F stop down. I don't know why the light is so tricky from that location.

5 nights great!

OK location. Anything in the park is ok, but this is my least favorite.

Route to YNP. Take US89 up through Tetons.

Sights en route. Tetons, which are south of YNP. Great Salt Lake is right by the airport. A short exit on I80 west will take you to Saltair and a tourist center. Short visit will chalk off seeing the Great (& smelly) Salt Lake.
North along I-15 is Promontory, where the Golden Spike Nat. Monument is located. This is the place (no pun intended) where East met West and the continent was connected via rail nearly 150 yrs ago. Worth a trip.

Temple Square (really, a 1 block square) in downtown SLC. Ground zero for the Mormon church; 1 hour visit would give a sense of Utah's history.

Park City is 30-60 minutes away. If you take I80 East you can head up to YNP via Wyoming. There is another National Park, Fossil Butte, in Kemmerer, WY (also home of James Cash Penny and his chain). Interesting for fossil fans.

West Yellowstone is a fun touristy town. On you way home, you may want to stop there.

Car rental advice. Hertz Gold. Best program going. Sign up now.

Also, make a dinner reservation (make a few) now for dinner at Old Faithfull Inn . Typical NPS lodgepole pine Inn. {Stay there if you can!!!]

We stayed at Grant in 94 - it's just a "no frills" place - but the location is nice being on the lake. We enjoyed the restaurant there. Since it's your first trip 5 nights will do you. You can spend plenty of time in all the different sections of the park.

Grant Village is a motel like accomodation on the south end of the park. I would try to get reservations somewhere else in the park for two or three of the days. A room or cabin at Lake Hotel or cabin at Lake Lodge or a room in the Old Faithful area. Maybe a room in Mammoth, which is at the north end. We much prefer to stay in the park. A room at Canyon is also a possibility, it is also motel like, but is different scenically. You could even get a cabin at Colter Bay in the Tetons and stay there on the way up or way back. Call Grand Teton Lodge company. They usually have cabins available this far ahead. If you go to the Tetons first I'd drive from Salt Lake up I-80 to Evanston, WY, take 89 through Woodruff, Ut, Cokeville, Wy, Afton and up through Alpine to Jackson and on to Tetons. We love Yellowstone, I hope you have a great time.
Tony

Tony has definately given you the best advice..and also the best route to Yellowstone...Myself, I doubt you will be able to find accommodations at Mammoth, Canyon, Old Faithful, Lake Lodge , or Jackson Lake Lodge for these dates in July..It is worth a try..but hang on to your reservations at Grant Village.. be certain to have another reservation in hand before giving them up...