I don't personally like Pedigree or Iams. The main reason I won't feed Iams is because of the cruelty that went on there.
IamsCruelty.com
As far as Petsmart goes - By Nature, Castor & Pollux, Blue Buffalo and Wellness come to mind.
I, in my non professional opinion, like to stay away from by-products, unnamed meat sources, soy, wheat, corn, preservatives like Ethoxyquin and menodione.
Some sites to use just as a base -
www.dogfoodadvisor.com and
www.dogfoodproject.com are good references. Don't worry if a food is a "3 star" or whatever though... I don't much pay attention, I am more concerned with the company behind the food, ingredients, and how well a dog does on a food.