Disrespecting your parents
Disrespecting your parents is not a good move. They brought you into this world, love you with all their hearts, and try to do what is best for you.
I may have disagreed with some of the things my parents said and done, but I still love them, and always will. They are the only parents I have, so treating them with respect is wise.
Parents really are not bad people. They may make mistakes sometimes, and they may make the wrong choices, but that is because they are human, and making mistakes is a part of life. They learn from that, and move on.
They became parents for a reason, so don't disrespect them. They love you very much, no matter what.