Siesta Key is the way to go for you!! Great dining and a good nightlife especially on weekends.
Tropical Breeze is the right choice. They have a few accomadations right on the beach but most are about a block away (an easy walk with chairs, etc...). Also it is located behind The Village and you won't have to drive anywhere for bars and restaurants (Siesta Key police are VERY strict when it comes to drinking and driving, roadblocks on the bridges are common).
Bars: all located in the Village
The Speakeasy - live bands, nice locals atmosphere.
Gilligan's - large bar with indoor & outdoor area. Live DJ and dance music at night.
The Beach Club - Bar & restaurant with more upscale atmosphere. Also some live music and DJ at night.
Siesta Key Oyster Bar (SKOB) - Outdoor dining and bar. Live music, usually a one man band playing guitar (think Jimmy Buffet)
Daquiri Deck - offeres about 30 different frozen drinks, food. Indoor or deck dining.
The above mentioned restaurants are two of the best on the Key. There are many other's that are good as well. You and your friends will have a great time on Siesta. Plenty to do and you won't have to drive off the Key unlesws you want to go exploring or hit the downtown area. Hope this helps.