As advised by others, uninstall Norton using the Norton install discs, then let us know how your Mac is running. Not only do you not need Norton on your Mac, it could easily be causing slowdowns. If that doesn't help, run Disk Utility booting off the OSX install discs. Has anything been repaired? Do not attempt any kind of OSX reinstall until you've tried at least these two simple steps first.
i will consider. basically i want to buy an external hard rive and then just restore my computer. im sure it isnt necessary but you need to restore you computer once and a while anyway right?