Stalin lives longer for one thing. When he ruled, people adored him (Or Pretended to as to not be shot). He died at the age of 74, so maybe if he had a healthier life style, which would be our POD, he could live up to the 1970's as the dictator of the Soviet Union.
Perhaps with more time of him in power, he could eliminate a lot of the trouble that happened in the 60's and 70's. Maybe he could have crushed a lot of separatist groups in their infancy, and perhaps crack down on the Baltic States and Ukraine, which IMO were the main states which caused the collapse of the Soviet Union.
The 80's would be much like the 50's in the Soviet Union, strong growth, etc. A leader like Stalin would be more likely take power if Stalin died in lets say 1975. Stalin could groom his successor, and would rule with an Iron Fist.
I could see the Eastern Bloc surviving the 90's, but by 2000-2010, East Germany, Czechoslovakia, Hungary, Yugoslavia, Albania, and Bulgaria would likely have fallen to Democracy, and by 2005-2006, maybe Poland.
I could see however, the Soviets in 2005 trying to hang on to Poland desperately, and occupy the country.
As for its reputation and Democracy, by 2000, I see some democratic and economic reforms taking place, and by 2010, the government would be somewhat more democratic and peaceful with the West. Perhaps this could keep Romania and Poland in the Eastern Bloc.