Not sure I can meet your parameters, but I'll try.
The French Revolution was the result of heavy taxation of the French Third Estate, which included the important Bourgeoisie; and who had little voice in government. The wars of Louis XIV had left France heavily in debt; and rather than tax the First and Second Estates, Louis and his successors sold titles of nobility which exempted the buyer and his heirs from paying taxes forever. This in turn created an even greater burden on the peasantry. Napoleon came to power because of the volatility of the country following the Revolution. There was an attempt by other European countries to restore the French monarchy, and widespread famine which led to exorbitant prices for bread. A royalist rebellion was put down by Napoleon, after which he was sent to Egypt to stop the British. Since his army was loyal primarily to him alone, he was able to use it to gain power and name himself Emperor.
The French and American Revolutions on the surface were both fought over Enlightenment ideals, the basic rights of humans and the right of people to change a government which did not protect those rights. The American Revolution resulted in a stable government which has continued for over 200 years. The French Revolution did not establish a stable government. There failure of the Revolution led to the Reign of Terror, the Rise of Napoleon, the reinstitution of the monarchy, the dictatorship of Napoleon III and over history, the institution of five separate Republics.