Most common hernia to strangulate is :
"Of all the hernias, a femoral hernia is the most liable to become strangulated, mainly because of the narrowness of the neck of the sac and the rigidity of the femoral ring." - Bailey & Love
An epigastric hernia (or fatty hernia of the linea alba)

an epigastric hernia occurs through the linea alba anywhere between the xiphoid process and the umbilicus.
the mouth of a hernia is too small to permit entry of any hollow viscus into the sac; consequently, either the sac is empty (contain only extraperitoneal fat) or it contains only a small portion of the greater omentum.
Direct inguinal
Indrect inguinal
Femoral
Epigastric