I think I'd pick “Butch's” from “The Best Years of Our Lives.”
Of course, seeing as how it is set in the 1940s, cigarette smoke would be an issue.
Same goes for the place in “Harvey,” which would be another possibility.
Two that would not be high on my list are the bars in “Star Wars” and “Flashdance.”
And the George-Bailey-was-never-born version of the tavern in “It's a Wonderful Life” seemed to attract a pretty easily amused clientele. I'd steer clear of that place, too.