My wife and I went to Italy and Spain last year. I would recommend Barcelona in a second if you would consider Spain instead of France. However, I have never been to France so can't comment at all.
Regarding Italy, we spent 2 days in Milan and I wouldn't recommend more than that in Milan. It was big, dirty, humid and hot. Other than the Duomo (Catholic Cathedral in Milan which is amazing) and the Last Supper painting, there wasn't much that interested us. From what I have heard, that seems to be the concensus on Milan as well. However, you will be able to "save" $400 on a Prada bag if your girl desires one.
We also spent about 5 days in the Italian Riviera staying in Santa Margherita Ligure and visiting Portofino and the Cinque Terre. I absolutely loved that area, super beautiful, scenic and one of the most peaceful, calm, relazing and serene places you will ever visit. I wouldn't recommend staying in Portofino as it is VERY small. It is, however, very close to SML (which is actually closer to the trains and more accessible) and definitely worth visiting for a day (you can literally see everything in half a day). Cinque Terre is beautiful and scenic as well.
here is the wiki entry on it to explain it more. It is basically 5 towns (hence, the name) located right on the water, all very small that has a walking/hiking path from town to town, you can walk from the northern to the southern most town in an afternoon, I would recommend walking south to north (easier walk).
SML is like a small Santa Barbara if you have ever been there. Nice shops and restaurants, people are great, very mellow. there isn't a ton to do but if you want to relax it is 100% recommended. If you are looking to rage, look somewhere else.
http://en.wikipedia.org/wiki/Cinque_terre
