Try Knoppix from CD. Play with it to see if it suits you at all.
Check reviews for other distributions before you commit time to putting one on a hard drive. This thread has some very good suggestions.
If you are a serious computer hobbiest, try Gentoo. It is a PAIN to install, but the docs are good, and you'll learn more about the underlying software.
With the disclaimer is that I do unix work commercially so partioning, building software packages, configuring daemons is all second nature to me let me say that installing
Linux from Scratch is a PAIN. Gentoo is Linux from Scratch without the pain and suffering, but you do lose a little ability to customize.