The valiant people that tried to throw off the Nazi grip on their city,have the Russians to thank for losing the battle.Just a few miles from Warsaw there was a large amount of Russian forces.Stalin held them back so he could get rid of the democratic leaders and fighters,so Poland could easily be made a Russian satellite.
Tanks versus horses didn't happen.They fought dismounted.
The reason the Germans did so well with their "Blitzkrieg" was the fact they were the first to use close air support to their advantage.German tanks weren't that great,as France had better tanks,and more of them.The Germans had Stukas,and knew how to use them.
If the French would have launched an attack on Germany as soon as the Germans attacked Poland,now we have a war on two fronts,and Hitler found out later that isn't a good thing.