You want to write your own programs? Learn C++.
You want to be a *hat? Read: HackerProof, Maximum Security, Art of Deception; there are many others but those should give you a referance point.
You can "hack" with any operating system so long as you have access to a *nix shell; think of investing in a moderately cheap computer (P200+) for linux pourposes.
For note, white hats don't generally hack, they secure (or at least their not known for hacking in a general sensus)...