The introductory programming course's language of choice at my university was C. I have mixed feelings about learning C as a first language. I remember the people who go it right from the start benefited the most and got a good base for the rest of their programming learning/experience. But the people who had trouble grasping some concepts of C, got stuck with that and later ended up hating either C or programming altogether. (Disclaimer: this was a class full of all kinds of engineering students, not just CS).

Anyway, I think C could be an excellent second language to learn. Starting with something having a similar syntaxis like Javascript could be a good choice and pretty helpful in the future too. Plus, you won't need an IDE, a compiler, setting up a server or a database, only a browser.