I was out that way last Fall around the dates you propose. We were based in Ouray.
We were up on Owl Creek Pass Road, in the Uncompahgre National Forest, at the Black Canyon of the Gunnison, Mt. Sneffels along the Dallas Creek drainage/Miller Mesa, and up on the Last Dollar Road on the way into Telluride.
Here's my gallery from that trip:
http://www.pbase.com/pauls/colorado_fall_color_2004Peak fall color is hard to predict and the exact dates will depend greatly on local conditions. We hit it a little late but the compensating factor was snowfall earlier in the week which gave us some great contrasts between the snow and aspen color.
The Forest Service has a fall color website (this is last season's, hasn't started for this year yet):
http://www.fs.fed.us/r2/recreation/fallcolors/Best,
Paul