My wife just had the staples removed following her c-secrion. The skin separated a bit. Will that mean she will have more of a scar?

Possibly. If it's a slight separation, usually steri-strips will help the incision heal well. However, if the wound opens, this may have to heal "secondarily" meaning it will have to heal slowly from the bottom up (with or without packing gauze) and this may leave a thicker scar. Either way, call your doc's office for instruction and to prevent infection.
Maybe. It is important to prevent infection-that really makes a scar bigger. With your surgeons permission I would recommend some otc antibiotic ointment to soften scab and keep wound covered.