Hacking in general.....
Well you could learn C you could learn PHP, you could learn about TCP/IP, you could learn how to use Backtrack and related tools you could get yourself a linux/unix and learn to use it. You could learn to obscure yourself and your machine using proxies, vpn, ssh, tor, browser spoofing, you could learn C# or something and create little video game modding apps. You could learn to be like techb and turn a toaster into a robot that cleans your house and alerts you any time your nick is mentioned by anyone at anytime anywhere in the world....
But since you don't seem to know what you want or what you mean by hacking I might recommend Python or C. Python is a user friendly programming language that is great for beginners and despite what many people will say C is just fine if your not retarded. They teach it in high school so it's not only for the 1337est of people. Once you get going with that you will figure out what you want.