Perhaps the most important thing to say about Napoleon's domestic policies is that they were aimed at giving him more power. Napoleon created a domestic government where government officials were present in every town of the country and all of them were loyal to the central government (which Napoleon himself controlled). Napoleon reinforced this control by banning any kind of dissent against him.
Not all of Napoleon's policies were so oppressive. He did help to build industry in France by loaning money to businesses and by creating a better infrastructure of roads, bridges, canals, etc. He instituted public education. He tried to make sure that people from whatever class could get ahead. But even all of these things were mainly aimed at strengthening his own position at the head of the government.
Please follow the historyguide.org link for a very detailed discussion of his domestic policies.