Have to second the good advice about considering moving from area to area when visiting Yellowstone/Grand Teton. Even in the fall when traffic is light, you are going to, no matter what, end up behind a sixty foot RV going around 20 mph for MILES and MILES and MILES with no chance to pass safely. While I admire those with such magnificent rigs, they can make what would logically seem a half hour drive (22 miles?) into a less than magical adventure.
In reality, the scenery on the roads is part of the park experience, they aren't just paved conveyances to jet from one point to another as fast as possible, and, well, if your view is blocked because you are in a parade it isn't as magnificent. The parks are for all to enjoy, so those monoliths have every right to be there, but you can really set yourself up for disappointment if you think in one day you can start out at Jackson Lake Lodge (which I highly recommend...we had a moose and his mother lying next to our patio upon arrival) then visit Old Faithful, then Mammoth, and stop and see a few bubbly pots en route, and then try to return where you started from!
We stayed one night at Jackson Lake Lodge, then Snow Lodge, then a motel in West Yellowstone, then back to a rugged western style motel in Jackson Hole. And it still wasn't enough time to drink it all in. But at least we didn't spend hours retracing our paths...we got to see many fabulous places that made you so grateful no one could put up a strip mall with a nail salon and a mattress store for a thirty mile + radius.