Lenin wanted to incite a world-wide revolution. A total upheaval of every society on Earth. The Lenin didn't plan on making a communism in a single country, like Stalin did. He wanted a world-wide-revolution! That means he would have used all resources in Russia to fund and man revolts all other the world!
Also, http://en.wikipedia.org/wiki/Polish%E2%80%93Soviet_War notice the dates here and http://en.wikipedia.org/wiki/Vladimir_Lenin
1920 for war and 1922 for Lenin dying. So war with Poland was under Lenin's rule. I doubt Poles would be friendly with a leader of a country who has just tried to re-conquer them with military force.
That was fresh on the heels of the soviet civil war. This was a war over land that very, very recently had been part of the Russian state. Lenin was a man of bloody times. Stalin was a man who created bloody times.
And it's not like the Poles would particularly need to like the Soviets for Hitler to be checked. They just need for the Russians to pragmatically avoid helping the Germans. Stalin was very... unusual for striking a deal with Hitler. If not for the Soviet alliance with the Germans it's pretty doubtful that Germany would have been willing to take on France and England and Poland alone.
And Lenin died in 1924 not 1922.
Isn't it the common knowledge that Churchill wanted to strengthen Germany (hence the Munich deal and the Phoney War), so that it will fight the Communists? Hitler would have attacked Poland anyway, since he was at that moment sure that UK would not intervene.
Also, Polish history of animosity with Russian people is very,
very long (at least since
1612). I doubt they would suddenly forgot all of it.
Also, Lenin did die in 1924 but, if you've read the article, it says that he in 1923 has suffered a stroke that left him bed-ridden until his death.