Need Step by Step Help

Hello,

I am really wanting to reinstall my operating system on my Dimension 8300.  I have had my system for about 3 years now.  I have the Microsoft Windows XP Media Centre Edition and this diskette that says DELL P/N F3920 Rev A00.  I am not sure of the steps in the proper order.  This is what I have for a system

 

Pentium 4 Processor (3GHz w/800MHz front side bus/HT Technology)

Channel DDR SDRAM at 400MHz (2x 512MB)

240G RAID 0 (2x 120GB SATA HDDs)

 

I think that is all the info needed to help me do this right.  I am just not happy with how my system is running right now and want to start fresh again...just like it came out of the box for me :)

 

Does anyone  have any information or a place that I can go to get idiot proof step-by-step guide so that I can do this on my own. 

 

Thanks for the help.