C is a really good choice. People will tell you that C is hard and so on, but I'll disagree here. C is surprisingly minimalist and in comparison to C++ can be picked up in a couple of months.
If you wanna learn any programming language, the best way to learn is to do. Delete those 20gb of books you've downloaded, they are useless if you don't have a clue/idea of what you'll be building.
Decide on something that you'd like to build in C. Whatever it is, it doesn't need to be overly complex, but also make sure it isn't trivial. You need to be passionate about it. So think hard. Once you've got your idea, familiarize yourself with C's syntax, idioms and conventions. You don't need to read 200 books for this. Pick up one book or just google around. Once you are somewhat comfortable, immediately start working on your project.
In the meantime, while familiarizing yourself with C, get an account over here projecteuler [.] net and solve the puzzels using C. Don't cheat. You'll just be cheating yourself. Good luck!
