I found this 'Napoleonic Source Book' to be a good and useful overview of the Napoleonic Wars.
Haythornthwaite has divided the book into 7 sections. The first 60 pages are a brief descriptions of all the campaigns from the French Revolution to the end of Waterloo. And brief is the operative word - there isn't much space to go into explanatory detail here. I find it useful - my interest is predominantly in the Peninsular War but I know very littleof the other French campaigns.
The second chapter is on the weapons and practice of War. I know this is a somewhat controversial issue. I did find Rory Muir's book a lot more convincing on this subject - but then he was a lot longer.
Haythornthwaite then tries to do a very difficult thing, he has a chapter on the nations involved in the war, dozens of them from grand countries like Prussia and Russia to tiny backwaters like Piedmont and Reuss. You can see the potential problems when everything from uniforms to structure is tried to be explained.
The three sections I like best are next. He has one with potted biographies of the main players in the war - a great starting point I think. He also has a section on the sources he used for this - I don't know about you but I love bibliographies and his has some wonderful new books I hadn't come across before, and finally a section on miscellanea which I have found very helpful - from various calendars and colours to artillery tables.
I think this is a highly ambitious project and Haythornthwaite has done a pretty good job of it.