Basically for the operating system just make sure that it is based on the Linux kernel (Backtrack/Ubuntu/Fedora) as Jason and Bobby said and then read up on some system calls and then shell scripting. As for the programming languages, I would probably pick up a beginner programming book in any programming language (recommend C++ or Java to begin) to learn the fundamentals of programming (data types, conditional statements, iteration, recursion, data structures, subroutines, etc...). Also, I would look up the basics behind how computers based on the von Neumann architecture work such as memory addressing, procedure call stack, etc.. Last but not least, read up on networking basics such as the OSI model, networking protocols and things of that nature. Books and google will be your best friends.