I love Butte! It is not Disneyfied but is a great town to visit. I'll be going through myself in late July.
Getting a pasty (meat pie of sorts) is a Butte classic from the mining days. I like Joe's the best on Grand Avenue, but I hear there are other choices. Pork Chop John's is another Butte classic eatery. This is a fried pork tenderloin served with mustard, mayo and onion on a bun. It's right down the road from Joe's.
In Butte, the University has a mineral museum (a big room) that is worth a stop. The World Mining Museum is hands on and will explain a lot about those derrick-looking things you see all around town. Downtown Butte is largely unrenovated and full of leftover charm from the boom years when the powers that be were trying to make it the state capital (notice the "1" on all the license plates, but the Butte backers did not win as the capital is Helena). The Berkely Pit is a large open pit mine that has some interesting things going on (algae that lives in extreme conditions, etc).
Our Lady of the Mountain is a famous landmark, and Evel Knievel is Butte's famous son. Knievel Days is on July 24, 25. and 26 this year so you'll miss it.
In the area, there are many hot springs (Boulder, Butte, Fairmont, Norris) and lots of great camping down by Dillon, Jackson and Phillipsburg. Lewis and Clark Caverns is over by Harrison, not too far from Butte, and the three rivers joining to make the Missouri River are all world class trout streams (Madison, Jefferson and Gallatin) at Three Forks.