How to uninstall xp from my computer?

Hi,i had a few problems with my computer recently like i couldnt connect to the internet because something got deleted by mistake..I tried everything but couldnt get internet access so i decided to load up xp again hoping it would load up what was missing to get internet access,but i seem to have xp it on my system twice now and have figured out how i couldnt get internet access in the first place so i want to go back to the way it was before i reinstalled xp again,all my stuff from before is still there so i just want to remove the latest installment of xp i did, but dont know how,i cannot do a system restore back to my previous version and cannot delete it from add or remove so could someone please help me get things back to the way i was previously set up.i'm a noob at this and should have left it alone and all i want is to have it back the way it was with all my stuff on the desktop instead of just a recycle bin,so can i remove the xp i just loaded yesterday.thanks.