If it helps you plan your trip any (and I doubt it will)...
I spent 4 days at Yellowstone a few years ago. Had a baby along for the ride so couldn't do much hiking, stayed at a hotel in Gardiner.
Got to the hotel Sunday night @ 8pm. Most of the restaurants were starting to close up. Moral = get there early enough to eat a decent supper.
Each day we got up around 7, out the door around 9, back to the hotel after dark, around 10pm.
1st day was spent driving down the "right side", as in the east side of the Grand Loop, Mammoth, Roosevelt, Tower Falls, Canyon Village, Lake Village, Bridge Bay. Stopped at almost each and every little turnout, picnic area, etc. Had lunch at Lake Village (great burgers), started getting dark, skipped West Thumb, went straight to Old Faithful to watch the geyser at dusk, had supper at Old Faithful area.
2nd day, drove straight down the "left side" (west side), thru to the Grand Tetons and checked that out. Did the Jenny Lake boat tour, did some walking around, had lunch in Jackson. On the way back, stopped and took a good look at West Thumb/Grant Village, then again, back up to Old Faithful for supper and another dusk showing of the geyser.
3rd day, back down the "left side", Mammoth, Norris, Madison, etc. Took most of the day to make it down to Old Faithful, but got there with plenty of time to walk around the Old Faithful area, see a bunch of geysers go off during the day, and again, ate supper there.
4th day, drove the cut-across between Norris and Canyon Village, re-checked out Grand Prismatic, drove 'side roads' off the Grand Loop, drove the east and west entrance roads, and had supper in Gardiner. Basically picking up the pieces of the areas we hadn't seen yet.
Next time I make the trip, I'm going to spend more time just watching at the Norris Basin and Grand Prismatic, as well as try to get to the Old Faithful area early in the morning.
Here's one thing that made me laugh for literally hours...
http://www.youtube.com/watch?v=prQ3t5FBYms" onclick="window.open(this.href);return false;
Over those 4 days, we didn't rush anything, always had time to do whatever, didn't feel like I was getting up too early or going to bed too late, and I still feel like I could've spent another day or two there...possibly another week or so if I'd had planned on doing any hiking into the back woods (which requires a permit and stuff, so a bit of a PITA).
How long you plan on spending?