my two cents:

don't worry about security, all your hardware, or even being productive with linux for a while. you need to learn the basics first. Oblivious had the best idea, buy a beginners book, learn the commands, install something like suse or mandrake, and just learn how to use it. you have plenty of time to play with word processors and security later.

and remember not to be shy asking for help, it's not easy to begin with. good luck!