The larger cities in Montana certainly have the qualities of typical "great" downtowns. You'll find a density of business, culture, and retail in Missoula, Bozeman, and Billings, but in Montana, I don't think that's what necessarily makes the "best" downtown.
It's one of the biggest party times of the year for adults, and no small thing for kids either! Halloween is coming up and we have a lot of events in the Missoula area this year!
Coinciding with this year's Brewfest will be this year's Daly Days - a yearly festival of western re-enactments, plenty of activities for kids and living history booths.