The general difference between them is Trotsky was obsessed by idea of World Revolution while Stalin understood craziness of this idea. Trotsky thought like man who has no motherland. Stalin was a patriot. Freedom is a strange thing. All the people have in mind different senses of that. Stalin liked soviet democracy but this is not the same democracy that western one.
He's the same one that Yeltsin. Maybe the only difference is he doesn't drink too much. Credulous people love him, but clever ones generally doesn't.
Trotsky, like Lenin and all of the original Bolsheviks was trying to continue the international world revolution of the workers started by Russia. They were fighting these idea of "motherland" and "patriot" that are put forth by the Capitalists who profit from war and will do anything they can to get people to join the army. I do not understand what you mean by "Democracy" except a Democracy in which hundreds of political opponents are executed and millions are slaughtered in purges. Stalin killed so many of the original Bolsheviks. Stalin also turned his own position into a dictatoral one with absolute power.