pacatelo is on about the bar scene. Hotel wise, I always recommend the Copacabana or Canciones Del Mar which are right next to each other directly on the beach...and easy short walk to the Beattle Bar;). Both have mostly or all suites with AC which is a good value. Do a "search" above to find more posts on these places with more info.
You also might want to try the new CR travel site
www.costaricatogo.com which has tons of info on CR hotels including Jaco Beach. They also have an online chat support for real time answering questions or booking travel here. Tons of videos online of CR makes this THE Costa Rica travel site in my opinion.