I still don't see that anyone has answered the question of baggage being ticketed through to final destination or not. If you have to pick up your baggage and check in for the final flight, that takes you out of the transit area, does it not?(original question 3) This a question to direct to the airline.

@nsammy--It is my understanding that the process for a tourist visa for an Indian passport holder may be considerably more rigorous than for a transit visa.

OP, if you need a visa and do not have one, your airline likely will not let you board the flight into Brazil.