Mesa Verde is a must stop. You can hike down to to Spruce Tree house without a ticket or a guide. There is also Cliff Palace, Balcony House and Long House. You need a ticket for those. Tickets are just a few bucks. For Cliff Palace they have a special tour in the evening. It cost a bit more but is limited to a smaller group and there is no one behind you pushing the tour forward. It is lead in theme. The one we went on the theme was the CCC. The ranger was in costume and all the info given was from the ccc period. It was great. He did follow up at the end with updated info.
Mesa Verde National Park - Evening Programs (U. S. National Park Service) twilight tour
Camping in the park and jsut outside the park.
Durango you have the Durango Silverton train. You can bus up train back, train up bus back, train both ways. Beautiful ride.
Home | Durango & Silverton Narrow Gauge Railroad Train
Many camping options.
Also several campgrounds up by and at Molas Lake area. Absolutely beautiful up there. Fishing hiking etc.
You have the alpine loop , 4x4 is a great idea but it is not hardcore. Drop trailer and go for it.
Alpine Loop Home Page
Hot Springs in Ouray. Camping in and around there.
Once you get up to Ridgeway you are not far from Montrose which is not far from Black Canyon of the Gunnison NM. There is a road that cuts over Owl Creek Pass that puts you out on US 50 just east of Black Canyon. Great scenerey and some nice hiking on the West Fork of the Cimarron, Middle Fork of the Cimarron river and east Fork of the Cimarron River. Silver Jack Resevoir has a decent campground (no hookups) but better check it out online to make sure your rig will fit in it. Or just take the Highway to Montrose and then US50 east to Black Canyon. Camoping in the park and nearby.
Obviously Telluride is worth the short side trip. Rico historic mining area. Some quick internet searching will give you ideas for that area as well as camping locations.
Also Canyonlands NP Needles District and Moab (Arches NP, Canyonlands NP Island in the Sky District and Dead Horse Point State Park) are about 120 miles from Cortez. Well worth seeing any of those areas.
Canyonlands National Park - Needles (U. S. National Park Service)
Canyonlands National Park - Island in the Sky (U. S. National Park Service)
Arches National Park (U. S. National Park Service)
Dead Horse Point State Park | Utah.com
Camping abounds in these areas just do some research for your needs.
If you like hiking there is lots of it. If you like fishing there is lots of it. If you like eyeball busting scenery there is lots of that too.
Depending on your route to and from - Monument Valley is cool. If your route goes through/close to Page, Arizona Upper or Lower Antelope Canyon is great.
Monument Valley Navajo Tribal Park
Also use above link for Antelope canyon look for it onteh website
antelope canyon - Google Search
Hopefully this will give you some ideas to look at and investigate to see what will fit for you and your family.