Guarulhos is an actual town, so has the amenities of a small town including restaurants, bars, etc. I've just passed through, so can't give specifics. Someof the hotels have free airport shuttles.
But with a 36 hour layover, I'd go into Sao Paulo city itself (about an hour)and stay there (unless you really just want to sit by a pool out in Guarulhos). Much more to do and see .....and eat. Try Jardins or Vila Madalena neighborhoods. There's a shuttle bus (about R$35).