I vote for French. It is the language of diplomats, and all UN documents are produced in both French and English. While there are a lot of Spanish speakers in this country, I can't think of any academic pursuits that would require you to speak Spanish. While there are more Spanish speakers than French speakers worldwide, the French speakers are spread throughout the world, whereas Spanish speakers are mainly in Mexico, Central America and South America (and of course, Spain).
All three of mine were in a French immersion school from Pre-K through part of elementary. Eldest went on to take German in high school, while middle kid takes Spanish. They both took/take French in HS, but were placed at a high level due to their immersion experience.
Italian should be easy to learn if you know French and/or Spanish. My two older ones can "read" Italian well enough to get the main idea of a story. Another thing to watch with Italian - if your school cuts a language, it will be Italian. Our district did this a few years back.
