i guess it really depends on what type of atmosphere you are looking for...
any of the bars at the hotel restaurants will be more of a rather calm environment but a couple of the places listed are a lot of fun to go to as well:
-jellyrolls on the boardwalk is a dueling pianos bar where the pianists play requests --- the only downside if you are a non smoker is that smoking is allowed and it gets rather smoky quickly
downtown disney probably has the most options:
-house of blues (usually has outdoor live act till 11) and bongo's cuban cafe only seats dinner till 11 but is open later for drinks (salsa dancing on friday nights) are both on the westside
-comedy warehouse (improv shows), adventurer's club (hard to explain, just make a trip there), BET (rap, hip hop club), 8track (70's and 80's club), Rock and roll beachhouse (rock and roll club, live band), motion (top 40 club), and mannequins (dance electronic club) all have bars, are non smoking, and are on pleasure island --- all better thursday through saturday
-MY FAMILY'S FAVORITE: Raglan Road in between West Side and Pleasure Island is and Irish pub/restaurant with really good beer and drinks; live Irish band, and Irish step dancer, and really good food to snack on (try the drunk chicken and guinness chicken wings!); reaturant serves till 11, bar open till 2 and can be a lot of fun
sorry this was so long but i hope it helps!!!
-plutolovr's DD21