Is the Disney Cruise Line worth it?

My family makes an average income don't get me wrong, but my family cant really afford a disney cruise. I really want to go on it and so does my sister and I feel like we are pushing my mom towards having a family cruise. I don't want to go on it if we cant afford it and bad things happen, but if it is really awesome maybe I can tell my mom that me and her should go. If it is worth it, what is the best cruise destination and boat? Also I know that and inside stat room is cheaper but is it really more amazing to have one with a balcony. My family does not know anything about cruises. Is there a month were it is really cheap or is there any secret promotional codes. Someone help plzz! Oh and is there another cruise line that is cheaper and the same amount of excitement for both kids and adults?