I used to live in Driggs, and my go to spot,once the Teton started it's long slow death, was the S.F. just below Palisades. The Grey's river(Alpine) can also be awsome. If you want to be tormented by some of the spookiest/smartest trout in the world.....Flat Creek in the elk refuge(5 minutes from Jackson) would do. I've fished it maybe 5 times, and never hooked a fish. It's only 10-20ft wide, and crystal clear. Large fish that come up eventually, and nose your fly, and go back down.....You could take the family out there for a "walk"...It's worth it just to see the large fish in their habitat, and maybe some elk will be down in the valley.

KK's suggestions were "spot on", and if you've never been to the Henry's Fork, then, what are you waiting for? Probably would take you 2hrs to get there from Jackson in October. While I've never been to the Lamar, I've dreamed about it...and once had a trip planned to go, but didn't materialize. I've also had a yearly discussion (20yrs) with my ID friend about doing the Bechler River(out of Ashton)....some of the most untouched wilderness in the country. I always avoided Yellowstone because of the crowds, but they will be gone in October, so there's endless possibilities there. Whatever you do, have fun....I'm jealous....Tom