I would suggest Python. It is supposed to be one of the easiest to learn and use, and in fact I myself am targeting that as my own first programming language. HTML is not a programming language, but rather a markup language. While it would be worthwhile and useful to learn HTML (or a variant, preferably XHTML), along with CSS and JavaScript, it's not really going to help you in the programming field.

As far as legal hacking goes, check out www.remote-exploit.org and download BackTrack if you want to learn some offensive security. I just burned my BackTrack disc today and I'm jumping in headfirst. It looks to be fun, and will provide a much better working knowledge of networking and security, not to mention the Linux operating system. Just be careful not to go trying to break into secured networks with it—use it at home as a learning tool. Like dsr said, if you want to be able to make money doing stuff like that, get a job as a security analyst. In any event, BackTrack is what many professionals in the field use. And it's an interesting Linux LiveCD to check out.