The challenge I've found in taking on a subject as an adult that I never studied in school is that I tend to learn it lopsidedly--e.g. learning all about the British side of the Napoleonic Wars, but little about the French perspective on the same events (not to mention the Prussians, Austrians, Russians, etc.). Really, I'd like to know more about French history in general, especially 18th and 19th century. But it's tough, because I keep getting hold of books that assume a greater degree of knowledge than I have, and I flounder through them without context or a big picture view.
The Age of Napoleon (Alistair Horne, 2004) added some clarity to my picture of French life under Napoleon, largely focusing on art and culture. It's a quick, readable book, something of a survey but not an oversimplification. I'm sure I'll be making good use of the reference list.