S.S. Aggie,
You should not have let shots or a visa deter you. We did our honeymoon in Brazil over 2 weeks last February starting with 5 days in Rio at the end of Carnival before moving on to Fortaleza, Salvador, Foz do Iguacu, and Sao Paulo. Since we were mostly in the cities listed, above we were not required to get shots. I would go back to Rio in a heartbeat.
To the OP:
Obviously see Christ the Redeemer statue. However, I would prearrange transportation to Corcovado with a reputable outfit. We simply grabbed the first cab we saw on the street. This had to be the biggest POS cab in the city. The statue overlooks the city from a mountain that has a favela (slum) at its base. We thought the scariest party of our trip was going to be when the cab driver stopped and got out at an intersection in the favela to talk to some dudes, thinking we were being delivered to them for robbing or kidnapping. That was until he got back in and we began our ascent up the narrow mountain road. Aside from the fact the cab sounded like it had a struggling lawn mower engine in it, we were flying around blind cures and corners where the road was about 1.5 lanes wide.
We finally made it up and then back to our apartment. To top it off, I left my digital camera on the back seat of the taxi, so we lost all our pictures from the statute and the Carnival parade at the Sambadrome. At least I still have the video.
Sugar Loaf is a must and is an easy cab ride from Leblon, Ipanema or Copacabana, the safer and more touristy part of the city. We stayed in an apartment 2 blocks off Ipanema Beach right where it meets Leblon, and we loved our location.
Spend some time on Ipanema and Copacabana beach as well as the shops and restaurants that line them. However, Copacabana, which I believe is a good bit longer, had many more than Ipanema. The same goes for the booths selling paintings, souvenirs, clothes, swimsuits, statues, etc. We picked up lots of fun cheap stuff there.
Help Discotheque is nothing more than an organized pick up spot for prostitutes. My wife was 1 of about 5 girls there not working. If you want to spend an entire night with one (or more) of the most beautiful women in the world for around $200 each then go for it. With that said, they had a good DJ, cheap bottle service, and it was the best people watching I've ever experienced. I'm sure we'll go back on our next trip to Rio.