French ships were known for having great lines (design that made them good sailing vessels) and this made them desirable to command if captured and turned over to the British Navy. But in terms of crews, the best way to put it is, "strong majority of the time, probably not (but sometimes maybe)."

The British had a tendency to engage in long blockades of French ports and to keep French Navy fleets bottled up at anchor. When the French crews are in port, they aren't getting experienced in sailing, let alone combat. Very few trained while in port. On top of that, their leadership may contribute to French crew ineffectiveness. The French Revolution dealt a pretty major blow to the French Navy officer class. Executions or fleeing France thinned the ranks of the upper positions for the French Navy. As a result, common ship masters (even from the civilian service) often had to step up into command positions in the French Navy. They didn't have the training of French Navy officers - they may be able to sail but are they skilled at leading men in combat and know their tactics? Over time, some captains adapted or got experience, and you got a group of good French captains, but it would be nothing like pre-Revolution France.

The good captains and crews that could equal the British were probably those that went to raid commerce or in small fleets to operate in smaller operations. They would be out gaining sea experience and getting crews to work together. But the number of crews that got that opportunity for this would not make it a qualifier for saying French crews equaled British ones. The British were more likely to have crews that practiced their gunnery and have crews made up of experienced sailors who had active sea service.

Want to know more and what my source is? There is only one book in English that covers the entire history of the French Navy until about World War 2, and that's A history of the French navy : from its beginnings to the present day from 1973 by Ernest Harold Jenkins. Beyond that, I'm just hoping that a Richard Brownlow Byington of Florida State University publishes his work on the French Navy to a book some day (his 76-page 2011 graduate thesis, that's in English, entitled "The Forgotten Service: The French Navy of the Old Regime , 1650-1789" is available online).

EDIT: I forgot to mention that there is a point in the Napoleonic Wars when the French get short of sailors, so they start putting soldiers onboard to fill crews as well. That should say something about the quality of crews.

Partially true, partially missing crucial points.

Though it isn't a focus of his book, Alfred Thayer Mahan does discuss the Napoleonic wars a bit in "The Influence of Sea Power Upon History: 1660-1783"

One theme that he returns to is that, generally speaking, the French had larger and more powerful ships with better tactical precision. He repeatedly speaks highly of the organization and precision in which the French fleets are commanded.

On the other hand, the English (tended) to have superior sailing ability and yes, daring. But it is worth pointing out that in naval warfare in the age of sail, "daring" is more than courage. Due to the need to rely on the wind, positioning and timing was crucial for fleets. "Daring" and "aggressiveness" means that the English were superior at taking advantage of these factors, as opposed to simple, if important, willingness to attack.

In addition to all of that, there are other factors worth pointing out.

To Napoleon, the fleet was a bit of an afterthought. He gave it considerable attention and resources, but its success wasn't a life-or-death matter like it was for England. Higher morale is just as crucial as the training of crews or the number and quality of this ships.

This is a bit more debatable, but Mahan speaks a lot about the "character" of the people. This comes up in how the British and Dutch needed to rely on their sea power for economic prosperity and military survival. In addition to the focus on navy that this provides, it means that England had a huge corps of fishermen and merchant-marine sailors on which to base their naval power. France certainly had fishermen and merchants as well, but again, the national focus was split between sea and land, vs the almost entirely naval focus for England.