What is considered the number one way or treatment for congenital heart defects or "hole in heart"?

Depends: Depends on the defect, but in most if not all, it would require a surgical intervention to patch it. The urgency depends on the type of defect, age and overall condition at the time of diagnosis.

It depends: About 1% of all children have some form of congenital heart disease, many of which are "holes" or defects between chambers. Most of these are very minor and require no treatment. Many close by themselves over time. A small fraction of the larger defects require repair, which can require open heart surgery or (more and more often) closure using a catheter (tube) inserted through a blood vessel.

Ped.Cardiologist: Need to undergo a complete evaluation by a pediatric cardiologist to determine the specific nature of the congenital heart defect. Only then a rational specific recomendation can be advised. It is not just a "hole in the heart", it is not that simple. There are many possible "holes in the heart" and associated additional abnormalities that are to taken into consideration for recomendation.