Re: Story of languages!
I don’t think that it is reluctance to learn, it is mostly not wanting to use that for official communications. Try to understand, all the south Indian languages have the status of classical languages because they have been in continuous use from antiquity. So people are proud of their languages. The Dravidian languages have nothing in common with Indo-Aryan languages and are considered as the original native languages. Another fact is that Hindi has never been in use as an official means of communication by kingdoms or the british before independence. Urdu yes but not hindi. So after independence, the proposal to make an alien to the south language like Hindi a national language was seen as cultural invasion. 
Most south Indians learn their native language and one non native language. Most opt for English since the dream is to work for MNCs or abroad not the govt of India unless one wants to become an IAS/IPS officer. Even then engineering and medicine trumps civil services as a profession choice for kids in the eyes of the parents. So learning another non-native language takes more effort since there is precious little time left over from maths and science. Funnily enough, Sanskrit is not met with the same reluctance. If India had decided on Sanskrit as national language like Israel made Hebrew national language , I don’t think there would be much opposition. People still learn Hindi from watching Bollywood movies. That is how I did.
I can understand hindi well enough but can speak only in broken sentences. In other words, my receptive language is better than my expressive language where Hindi is concerned. Last but not the least is the attitude. In my personal exp itself, I have had North Indians utter with consternation when I told them that I don’t speak hindi. They were dismayed by the fact that I could not speak the “national language” questioned my patriotism in not many words and proceeded to ignore me and another south Indian friend of mine by talking only in Hindi when we were around. I am proud to say that we tried to be more inclusive and used English to include them in our conversation and they claimed that they were not comfortable carrying whole conversations in English :D. Well this was almost a decade ago in my student days and the North Indians in particular were UP wallahs and I don’t want to tar all northies with the same brush. Now times are changing but I am not familiar with the education System in the South w.r.t languages but I can say that Hindi is still only used for govt signboards in offices and railway stations. But maybe the present generation is much comfortable with hindi than we were and hindi will slowly find acceptance. You never know , language is a very sensitive cultural symbol and we have had north-south “wars” and even south-south “wars” over language superiority. That is I think a fallacy of human nature.