I've been living in France since 1996 and I became a French citizen in 2002.
I'm going to beg, BEG, BEG you not to name him "Jean". My dh insisted on the middle name being after his dad, since our son's first name is after my father. Well, guess what it is?!?
It really bothers my son that his middle name is a "girl's" name in the U.S. even though he's born and raised in France. He's still American and it still bugs him. He really hates having to correct people in the States.
I would also urge you to avoid hyphenated names. They're out of fashion here in France and they can be a real burden for the child, especially if you wont be raising him in France.
I know a lot of French kids with a native English speaking parent. There are some names that don't work very well. Someone in an earlier post suggested "Emmanuelle". This is actually a girl's name. The male version is "Emmanuel" with "Manu" being the common nickname.
You may want to avoid names that are too similar with girl's names as some little boys I know have found the constant corrections and misunderstandings a headache. Other examples would be Emile (especially since Emily is so popular), Rene, Stephane (a friend was constantly mistaken for "Stephanie" in the U.S.), Gabriel, Michel, Dominique, Claude, etc. Philippe and Etienne have been confusing for English speakers too (guy or girl??) The "e" at the end of some boys' names can make it look girly.
I know a ton of Louis's, Alexandres, Vincents, Victor's, Paul's, Eric's and lately, a bunch of Elliot's. Sebastien is a name I've always liked (that's the French spelling).
We actually picked a Breton name, Ronan, since it works in both English and French well. You hear a lot of Breton names all over France, some are similar or the same with the Irish, another Celtic culture. He's named after my father, who was Ronald but I didn't want him getting stuck with McDonald's jokes and comments about immoral presidents! So we found something similar that wasn't a saint's name (we're not Christian, another criteria-although many are very nice!)
I tried so hard to avoid the "Jean" but I couldn't convince dh to change it to "Sean" or Johan or anything that wouldn't be mistaken for a girl! I'm very sensitive to this subject since my own name is unisex and I hated getting mail addressed to "Mr." and asked why I had a boy's name...