IMO, Leblon is the best neighborhood, Ipanema second, and Copacabana a very distant third.

I always stay at the Marina Palace in Leblon, there's also a more luxurious Marina Suites right next door. Then there's the Caesar Park in Ipanema (now a Sofitel hotel). All are beach-front, luxurious and excellent.

Then there's the iconic Copacabana Palace, a relic from the gloriuos past.

Here's a good deal on the Copacabana Palace

http://www.luxurylink.com/inventory/...tout=&guests=2