Dimension 5150 Restore

Hello,

 

I would like to bring my PC back to its original configuration. I know of the F8 option that brings the PC back to factory settings but what about a clean wipe of the hard drive? Is that an option? How difficult is that to do? Am I going to have to re-partition the Hard Drive? How difficult is it to set up my cable modem back for internet?

 

I have a Dimension 5150 running Windows XP Home (SP2). I have the Reinstallation CD that I purchased with the computer. Your help is appreciated.