Granted WW-II is the most common example of Russia saving the world from anything, that isn't what I had in mind with the OP. What I DID have in mind was Putin turning Russia's computer hackers loose on that East Anglia Climate Unit which in fact did have the effect of bringing the global-warming lunatics into widespread disrepute and stopping any chance they might have had at shutting down most of the world's economies for the glory of Gaea, as they would like to do.
Where we might be right now other than for that action would probably be nobody's idea of fun. Our own pols were either for greenism or totally cowed by it, Putin is the only guy who stood up to it.
Russia's only contribution to the allied winning of WWII over Germany's armed forces was only that they sapped far too much of Germany's military might at exactly the right time for us. But they did not do it for that reason.
It was Hitler's biggest and most obvious mistake, (two front war) that made it possible to end the war early without using nuclear weapons which were under development and would have been used otherwise..
So they kept the Germans busy....for a short while while we amassed a arsenal and ended it.