Is there a different way to start the heart if it suddenly stops without using a defibrillator?

Yes. Occassionally a precordial thump i.E a punch in the left chest can do the job. However, often a defibrillator is needed.
CPR. CPR is less effective, but better than nothing. Recent studies show the use of bystander CPR alone without giving breaths is as effective or perhaps more effective than wasting time giving breaths. Of course if the patient has something obstructing their airway, it has to be removed (heimlich maneuver).