Looking at pet stats forum postings, it appears that pet stats like strength, intellect, etc affect *pet talents* only. Having a high strength, for example, will affect the bonus a damage talent like pain giver provides, but a high strength doesn't directly increase spell damage. My locust swarm spell, for example, is doing the same damage regardless of my pet's strength until my pet gets a damage talent - then and only then does the pet's strength value affect spell damage.
Right. "Selfish" talents increase the stats of the pet, but do not directly affect the wizard. Higher pet stats increase the strength of talents that help the wizard, such as resist, accuracy, or damage, and they can reduce the cost to cheer in derby races.
