A full-service oil change is a more comprehensive service than an oil change. In addition to changing the oil and filter, a full-service oil change also includes a tire rotation and a safety inspection.
An oil change is just changing the oil and filter. Therefore, a full-service oil change will cost more than an oil change because it includes additional services.
An oil change is a good idea if your car just needs the oil and filter changed and nothing else. A full-service oil change is a good idea if you haven't had your car serviced in a while and it's due for a tune-up.