The Russian handling of Napoleon's onslaught was very skillful. In a major confrontation, Napoleon most likely would have won. Instead of fighting, the Russian's scorched-earth policy, in which they retreated and burned all the farms and other resources left behind, seriously hurt Napoleon's army. The Grand Army was so large that Napoleon did not supply it with supply-trains; instead, it generally fed and maintained itself by taking what it needed from the land it occupied. The scorched-earth policy left the Grand Army little to feed itself. Starving and cold, the Grand Army marched deeper and deeper into Russia, walking into ruin.
Interestingly, at the same time France was fighting with Russia, Britain became embroiled in war with the US. With the Continental System and British blockade competing to shut down trade in enemy countries, the United States found itself unable to trade with either France or Britain. Napoleon lifted the ban on US shipping, in exchange for a promise not to trade with Britain. Britain retaliated against the US in the War of 1812. The war ended in a standoff, effectively establishing the United States' sovereignty in the Western Hemisphere, as eventually articulated in the 1823 Monroe doctrine. Yet though the war certainly sapped British strength, it did not have nearly the staggering affect on the British that the Russian campaign took on the French. In fact, it is perhaps because of the events in Europe that the British did not fully commit themselves to war against the US, and the US was able to achieve the result it did.
After Napoleon met with defeat at Leipzig, the victorious powers began to fight amongst themselves over what to do with France. Alexander I wanted to put his own puppet king on the throne and the British wanted a Bourbon back on the throne. In November of 1813, Metternich announced the "Frankfurt Proposals", proposing that Napoleon should continue to rule a weakened France (Metternich knew Napoleon would be indebted to Austria for this). Napoleon rejected the offer. Britain, frightened of such a possibility, immediately dispatched Viscount Castlereagh to the continent to negotiate for England, and to advocate putting a Bourbon on the French throne. Metternich and Castlereagh immediately teamed up, secretly agreeing to prevent Russia from becoming to strong. The four powers signed the Treaty of Chaumont, promising to remain as allies for 20 years to stop France if it ever became too powerful.
The Treaty of Paris, which restored France to its 1792 borders, was surprisingly mild. Instead of destroying France, the great powers of Europe wanted a stable, normal France that could help preserve the delicate balance of power that European peace depended on. In terms of land power, the Treaty was a great success, establishing such a balance that no war broke out in Europe for a century. Even so, with its dominance of the seas, a growing industrial economy, and a vibrant colonial network, Britain emerged from the Treaty first among equals.