Stalin successes in achieving his economic goals were quite mixed. Stalin's main goal in regards to Russia's economic problems was to modernize Russia and industrialize because according to Stalin Russia was behind 50 to 100 years in compared to other nations in the world. In the long term Stalin was quite successful in achieving his goals. Russia went from being a country that was very behind in terms of industry and its economy to one of the World's superpowers in 1945. However at the start of his plan to modernize Russia and improve its economy Russia was not Stalin did experience some failure in between the time that this occurred. Collectivization for example was yielding less production than before thus hurting Russia's economy.
In regards to Russia's social problems, Stalin was both successful and failed at solving them depending on what standpoint you look at it from.
Viewing it from Stalin's perspective he was successful in solving Russia's social problem of traitors. Through the purges and the great terror Stalin virtually removed all of his opponents. Additionally, through this method of terror he was able to gain control of the masses and control all aspects of their social life. So, yes in Stalin's point of view he was successful in "solving" what he believed to be a social problem of the country. From a historian point of view Stalin was unsuccessful in solving the social problems of his country because instead of providing a country where citizens felt safe and secure, citizens were terrified of being killed, sent to the gulags, and of starvation.
Hitler was very successful in revamping and reviving Germany's economy. Before Hitler's reign, Germany's economy...