Yes, Son Goku is a better fighter than Vegita, because Son Goku fights with honor. Son Goku fights for honor and for principles. Son Goku never really fights to hurt anyone. The same cannot be said for Vegita. Goku is a positive example for young people to model, and Vegita is not.
Son Goku has a great attitude toward many things young people should aspire to have. His fighting style is sport like, so there is no malice when he fights. He only likes to win. Goku's general attitude is cheery and energetic other great attitudes for young people. He also has a great intuiton to see the good in other people. Although he is a fighter he does not fight without reason. Son Goku is an all around great anime role model for young boys.