Single itinerary booked on ebookers Lima-Foz do Iguacu-Rio de Janeiro-Lima(2 stops Sao Paulo and Buenos Aires). Im worried about my plane sw

Booked single itinerary w ebookers. Lima-Foz do Iguacu-Rio de Janeiro-Lima(2 stops in Sao Paulo and Buenos Aires). These are all on LAN and TAM airlines. Im worried about my 2 hour transit in Sao Paulo. I arrive in GRU Terminal 1 on TAM and depart from GRU terminal 2 on a TAM flight but operated by LAN Argentina.
1. Would anyone know if I could obtain all my boarding passes to Lima when I check in in RIO?
2. Would my bags be checked through to Lima?
3. Would there be airline personnel guiding transit passengers through to their next flights?
4. How long does immigration take in the morning hours?
Thanks

Asked by Emilio III via WorldNomads.com