As for the night spots, anywhere on Duval Street is fun and loud, full of energy. Since there isnt much "beach" land in the keys, I personally like The Reach hotel, or its sister property Marina. You didnt state when you are visiting, but either hotel is VERY nice but the Reach has the only exclusive beach. There is also Pier One (?) right by the actual Pier (of course) at the end of Duval Street.
Remember the Keys is just a BIG circle type Island, but everything at night happens on Duval Street, the closer you get to the pier (where you watch the sunset) the hotter the places get.
Hope Ive been able to help. Have FUN
2. Jessica P
If you are trying to get a hotel for Guavaween, give it up all hotels are booked until after the festival. If not, then Parrot Key Resort is awesome
3. Ana D
stay in your car, hotels arent worth it down there, they have lots of cockroaches