How many nights will you have in CO?

Well, they are all good just depending on what you want to do.
Mesa Verde/Durango
Rocky Mountain National Park
Garden of Gods/Pike Peak-you could see The Great Sand Dunes too

I don't have a favorite. They are all very different, but each one is great.

of course, you have all the resorts as well-Breckenridge, Winter Park, Crested Butte, etc.

I think I would hold off until Sept for the fall folliage colors.

You could go to Estes Park by Wednesday night. It will be longish drive, but not impossible. Or go to Boulder the first night.
Take a tour of the Celestial Seasonings plant there, and then head up to RMNP. Stay the night in Estes. Drive through the Park and back down to I70. Friday night somewhere?
Now you have Saturday to drive to Garden of the Gods and CO Springs. Drive home Sunday. Another long day, but doable.

Be careful - not sure what " we both have foot issues" entails [and you don't have to explain here] but check with your doctor re: high altitude, high temps in August and potential swelling.

PeaceOut, we will be there 4 nights and 3 days.
Spirobulldog, September and the foliage sounds wonderful, appx when do the leaves change?
Gretchen, your itinerary sounds great. We really would like to do a 1/2 day rafting trip and relax in a hot springs. Any suggestion to work those activities in?
DebitNM, no swelling issues, but thank you very much for the warning.
The 3 things we really want to do are: rafting, hot springs and see the mountains. Is there one part of the state that might be best for these activities?
Thanks!

You can raft, hot spring and see mountains all in the Durango area. Mesa Verde NP is there as well and is worth seeing. Million Dollar Highway would give you stunning vistas. The town is really laid back and has nice restaurants that won't break the bank and several choices as far as hotels. You can take the Narrow Guage Rail Train too, for another way to seen the mountain views.

FYI -water levels drop as the summer progresses and there wasn't all that much snowpack this year, so that lowers water too. I don't think your really want whitewater rafting in any case, more a float kind of trip.

I'll check into Durango. Laidback is definitely our style and we love good food. We are interesting in whitewater rafting, always wanted.to do it. Is it nonexistent or just really tame due to the low water? A mountain town is more appealing to me than a city...if that makes any sense.

That late in the summer, it will be fairly tame unless we have lots of rain during monsoon season. That hasn't happened in over a decade though

Tremble Hot Springs, hotsprings also in Ouray.

Apple Orchard Inn for a nice B&B

This is a bit dated, but almost everything is still around:

http://www.fodors.com/community/united-states/durango-restaurant-picks-by-debitnm.cfm

Probably no rafting. And I think Durango is too far for your time period.

I agree Durango might be too far to drive for this trip.

Check out Steamboat Springs. It has everything you want, and is definitely 'laidback', plus hot springs. I would drive there and stay there for your visit.

From Colorado Springs you're only an hour to Cripple Creek? It's an historic mining town, they have a narrow gauge trail, museums and it's also on a Scenic Byway, to give you a really nice drive in the mountains.

http://www.visitcripplecreek.com/businesses/auto-tours

Oh, Steamboat is a good idea for the springs, and they could actually do it going through RMNP for a scenic drive.