I posted this a few years ago. I imagine most of it is still valid:
Anyway, you asked about bars.. so let's start with Frisco.
The favorite local bar with lots of character is the Moose Jaw located on Main St across from the gas station. "Lots of character" could be taken to mean dive bar. A pitcher of Michelob will run ya $5 during happy hour.. a great start to any evening. They also serve a decent burger for a good price.
Assuming you stumble out of there and want to find more entertainment, head either direction up or down the street. Blue Spruce can offer a very nice atmosphere (complete opposite of Moose Jaw) with a nice upscale restaurant. Whereas you'll meet lots of ski instructors and lift mechanics at Moose Jaw, you're more inclined to find resort VP's at Blue Spruce. If that's your scene, you'll probably stay all night. If not, head the other direction down Main St. and stop in at Johnny G's. Darts, pool, live music, cheap beer and other sinfully good stuff can be found. It's hit or miss there, but generally I've found business doesn't pick up till 9pm or so.
From there, keep going to Barkley's. It used to be one bar with one owner in two different buildings. Now it's two bars with two owners in two buildings.. and everyone will likely still be calling it Barkley's for a few years. Barkley's Margarita Bar has new owners that seem relatively boring. Business seems to have dropped off. Though, if you like NTN trivia you'll find it there.
The other side is now called something like, "The Chill" and I highly recommend it. It's sort of hard to find, but it's on Main St. near the intersection with 6th. They're doing an awesome Texas Hold'em tournament on Monday nights that's free to enter with cool prizes. They do lots of other cool events, the Frisco Disco on Fridays has been going for a few years and usually attracts quite a crowd. Saturdays they do an all request night. Last year they started Drinkin' with Lincoln - all you can drink for $5. They stopped doing it for a while, but they're going to start again.
Two other places get an honorable mention - Tuscato's and Farley's. Both are more restaurants than bars, but they're really nice. Farley's just opened, though they ran a restaurant at Copper for several years under the same name. This one is nicer. If you want a great steak and are willing to pay for it, go to Farley's.
New this year (2006), at least new management, is Backcountry Brewery. Previously I hated the place, but it's gotten a lot better and the staff is a lot nicer. I still think the microbrews at Blue Spruce are better (I think they're Pug Ryan's), but the Backcountry Brewery stuff has really improved. Business doesn't seem to have picked up since the previous owners pissed a lot of people off, but it should get better soon.
Dillon has less to offer. It's quieter, but I kind of like that.
Pug Ryan's is a nice place downtown in Dillon across from the post office. In my opinion it's the best microbrew in the county. Good atmosphere and in general a good crowd. They have good dinners, but you'll pay for it.
Arapahoe Cafe has a bar called "Down Under". You can get there by going to the back of the restaurant and down the stairs. It's right next to the Ptarmigan Lodge. I'd definitely recommend it. They have pub specials every night for dinner and you might get lucky and find a great meal there for a nice price.
The only other bar in town right now is Wild Bills (this name changed this past year, I forget the new one.) It's a block from the Ptarmigan Lodge. It'll definitely be louder and a little dingier than the other two places. It's a typical bar, but the restaurant is pretty good.
Other than that, you're driving. Maxwell St. is near City Market and it's ok. Ruby Tuesdays is near there and has the best drink specials. The Cala in Summit Cove is worth going to. In Silverthorne I'd recommend Murphy's Irish Pub or the Old Dillon Inn. ODI usually has a lot of people on Friday and Saturday nights for their live music. In Keystone I'd recommend The Goat (a dive) or Snake River Saloon (nicer.)