Help Me Choose a Language to Learn.

I live in the United States. I am fluent in English. I know nothing of any other language. I would love to know what the most useful language will be in the future. I'm going to be dual-enrolling soon at a local university, and I wanted to take a class which is unavailable to me.

Can you suggest a language? The only classes currently available to me through my high-school are Spanish and Latin.

In north america the 3 main language you need to know is
English
French
Spanish (more spanish than french if your near the south border)

if you want to travel to europe you could learn other but with french and english you could work your way out of any situation easily.