[kls]

While basic is a good language to learn the (pardon the pun) basics of programming, it's not a great language to learn computer science if that is your goal. For that I think the best two languages you can learn are C and then Lisp. Neither are huge languages as far as number of jobs go but both are fundamental and foundational languages. Mastery of both will allow you to master any other language quickly. C will help you understand the hardware and Lisp will help you understand pure software CS theory that is why I recommend C first and then Lisp, you want to build a foundation, then layer on from that foundation and the best way is to work from the hardware up. Once you understand how the hardware is controlled by the software, it makes it very easy to see how to optimize code when you are dealing with what looks like pure software problems.

The Arduino board has a lot of support and following, so that is why I recommended it, and it supports other languages as well so as you grow and learn new languages you can use your knowledge of the board to learn new languages on. If you find a different board that you like though and it has a C compiler then it will suffice, but Arduino does have a huge community that tend to help each other out.