It's a litle hard to choose indeed. But if I were you, I would go for the first option. One can say that he took the power to himself, establishing a new coort, where the highest figures wore silk socks and had the same vices and flaws that the nobles of the Old Regime had. In that sense, yes, he betrayed the Revolution, to which he owes his rising.
However, one has to look to other aspects. With him as Emperor, France was quite different than it was in 13th July 1789. And I'm referring to the organization of the state, and the reforms that he took. The Civil Code, for example, was introduced during Napoleon's consulate. The establishment of the Bank of France is another important thing. This may not be the first thing that comes to mind when we think of "Liberté, Égalité, Fraternité", but it is is a mark in terms of the definition of what was now the national property. Offcourse that in the other side we have a progressive diminishing of the personal freedom and various civil rights were not respected. (At least it was still better than in the phase of the Terror a few years before).
Well, I agree that this is not enough to justify my choice. By the contrary. But, let's focus on his campaigns. They were terrible for Europe, and at the time were the most bloody ever. However, it was these campaigns that spread the ideals of the revolution throughout Europe. The main vehicle was not Napoleon himself neither his generals, but rather the common soldier and the low rank officers. VoodooAce mentioned the example of Beethoven, to show how the opinions about Napoleon evolved: from the champion of the Peoples that was breaking the chains of servitude, to the later tyrant against whom the entire Europe fought. But, the fact remains, that wherever the french army went, the original ideals of the Revolution were spread and assimilated by the population. What were those ideals? The ideals of Liberty and the right of the Peoples to dispose of themselves. The spreading of these ideals was exactly the reason why, in the 1820s and 30s, liberal revolutions happened everywhere in Europe.
So, Did Napoleon defend or destroy the ideals of the French Revolution? Well, like I said, this a tough one. But, "Was Napoleon responsible, or were his campaigns responsible for the spreading of the ideals of the French Revolution? Absolutely.
The French Revolution is an event of the most importance in the History. It is the event that begins the Contemporary Age and the modern world. So, to conclude: if it wasn't for Napoleon, the world of today would be completely different. And the world of today was very much built on top of the French Revolution.