If you are looking for the least stressful route, I-70 west to Grand Junction, then south on SH50 /550 is the way to go. Not much to look at in the way of scenery until you get past Montrose. It's 4 lane open highway from GJ to Delta. If you are driving at dusk, be especially careful south out of Montrose as this is the heaviest deer population in the state and you will see no less than 50 deer along the side of the hwy.
Hwy 50 from Canon City by Blue Mesa reservoir to Montrose is the most scenic route, however it is two-lane 90% of the way and lots of dangerous passing by impatient motorists. There are lots of places (scenic pullouts) to stop if you are not in a rush and well worth the travel.
Ouray is one of the most beautiful small towns in the state. We also took a tour of the Bachelor Syracuse Mine (5 minutes north of Ouray city limits) where they take you a mile into the mountain on motorized mine cars. Cascade Falls Park in Ouray is a nice short walk in the city limits. The Box Canyon is a must (south end of Ouray) and if you have time, Telluride is a 45 minute drive and well worth it. Ralph Lauren's Double RL ranch is on the way (SH 62 out of Ridgeway) and the views are spectacular! County Rd 9 is a public land access Rd and allows you to pass through a portion of the Double RL. County Rd 9 is a dirt road and not suitable while towing but an excellent excursion just in the TV. While in Telluride, you can take the free gondola ride up over the mountain to Mountain Village. Lots of neat shops there.
We go to the Telluride Film Festival every Labor Day weekend to check out the Hollywood faces in the crowd.
I'm certain you will have a great trip and create a lifetime of memories!