Well the Ten Commandments at 10 laws that God gave to Israel. These commandments are a basic summary of the over 600 laws of the Old Testament. The purpose i think is to prove to us that we can never perfectly follow God laws therefore we need his mercy and grace. They show us that we have all sinned and need JEsus Christ.
To be blunt on your second question I would say that Jesus is the way the truth and the light and without him you will not go to heaven. It is cut and dry :)
