I thought it might help to get a female persective. I lived in Montana (Missoula) for 7 years and I absolutely loved it. Bozeman is an awesome place too. The only reason that my husband and I aren't back there is that good jobs are hard to come by and the cost of housing is high. But if I had a good job opportunity I would move back to Montana is a heartbeat!!! The boating around Bozeman is great and the boating in Missoula (5hrs) is also great. Here are other perks: Yellowstone Nat'l Park is practicly your back yard, there is awsome skiing and riding all over the area. The hiking, backpacking, snowshoeing, etc. is fantastic! Everyone is really nice and the women totally out number the men. So, if you are looking to date you will have the upper hand. :-p
I have heard good things about Boise too but I just know that I left part of my heart in Montana. Oh, the Lochsa is a 2 hour drive over Lolo pass from Missoula. There is also Glacier Nat'l park in Montana, which is 3 hours North of Missoula, not sure how far the drive is from Bozeman.
Anyway, good luck,