Do I have the authority to decide on my own marriage even if my parents don't approve of the girl I choose, while I believe she is right for me?
As far as the conditions of marriage, only virgin girl requires the approval of her father or paternal Durand father for her marriage. Man does not need approval from his father or mother in his marriage, but it is very important to keep the respect of your parents and avoid hurting their feelings. You as a man are entitled to decide your marriage, without causing any harm or disrespect to your parents. You should try your best to convince them and get their blessings.
Wassalam.