restore Cd how to use

Tech-Archive recommends: Speed Up your PC by fixing your registry

Hi, my computer is under a year old and has norton protecting it,this is set
to automatic updates. How ever i have spent a week trying to get rid of
trojan feat 2. I have looked at various sites and downloaded several
including spy bot ad aware ectra but nothing is stopping my pages from being
hijacked and adds being thrown at me (normally for add stoppers and trojan
stoppers). I should like to restore my computer back to its original
settings. I have the discs but no information on how to use them. can any one
point me in the right direction please. many thanks
Irene
.