I recently bought fairly inexpensive plane tickets to SLC for the July 4th weekend. Reading the posts in this thread, I definitely should have planned things earlier. However, it seems like ~1.5 days in the Yellowstone/Grand Teton area might be enough for a first visit if planned right. So far I've planned things out as follows:

July 1st, 4:30pm: arrival in SLC. Rent car, drive to Idaho Falls. Spend one night in a hotel there.
July 2nd: drive from Idaho Falls through Grand Teton to Yellowstone. Probably mostly drive the main roads with a stop at Old Faithful and maybe one or two other stops in Yellowstone proper. Spend a second night in Idaho Falls.
July 3rd: (Half?) day in Grand Teton. Drive back to SLC afterward and spend night in SLC.
July 4th, ~9:30am: return to airport for flight back to SAN.

I also just checked and there still seems to be some hotel availability in West Yellowstone for the 1st and 2nd (albeit at twice the price of the Idaho Falls hotel). Would I be better off spending the extra money to stay at West Yellowstone and skipping Grand Teton this time?