We were there for 5 days, so obviously we had to pick and choose a few things. There's a ton to do in that area.
Hiked easy to moderate trails (
Potato Lake Trail was great if you have a vehicle that can get you up 2-3 miles of rocky, unpaved road to the trailhead)
Alpine slide and
mountain coaster at Purgatory,
Horseback riding (
the outfit we used is right across from Purgatory, but there are a ton of options)
Train museum in Durango (didn't ride the train because we didn't have time to fit it in this trip).
We camped a good ways south of Durango at
Navajo State Park. It was nice, but it's an hour from the mountains. We wanted to stay in a state park, so that's what why we settled on Navajo.
Ridgeway would've been my first choice, but it was booked.
We stopped at Palo Duro Canyon on the way there to avoid driving in New Mexico for long. It added an hour on the second day of the drive. On the way home we went through Santa Fe and across to Lubbock, which would've saved us time had we not blown tires on the road.