AFG: if you want to know how to overclock your computer correctly then you should read all the stickies in the processor and overclocking forums! I know -- I hate that answer too! But hear me out:
Regardless of whether you overclock your computer or not, your goal should be to understand what each BIOS setting means, how configuring BIOS one way is better than another, how part specifications effect your computer, and the effects of adjusting these specifications have on your computer.
You will learn so much through this process if you really take the time to read everything carefully! If you read the right documents carefully, you'll come away with a very broad understanding of computers in general and you'll come to appreciate things you would have never thought to consider when purchasing a computer or configuring a setting. Through your research you will become more adept at diagnosing problems, you will probably save more money when buying parts because you'll have a deeper understanding of each component of each product and how these components effect you. Lastly, I promise you that many of questions you're asking have already been answered compendiously somewhere else; these documents took whoever wrote them an exhaustive amount of time and effort to make, so they shall likely help you far more than something thrown together last minute in a thread like this.
Obviously, we're all happily willing to help you, but I promise you that you'll reach your objective more quickly by reading the guides and you'll learn more in the same period of time doing so in the process.
Just my ten cents.