Windows XP Service Pack 2
http://www.microsoft.com/windowsxp/sp2

Windows XP Service Pack 2 Overview
http://www.microsoft.com/windowsxp/sp2/overview.mspx

Release notes for Windows XP Service Pack 2
http://support.microsoft.com/default.aspx?scid=kb;en-us;835935

Changes to Functionality in Microsoft Windows XP Service Pack 2
http://www.microsoft.com/technet/prodtechnol/winxppro/maintain/sp2chngs.mspx

What to Know Before You Download and Install Windows XP Service Pack 2
http://www.microsoft.com/windowsxp/sp2/sp2_whattoknow.mspx

Windows XP Service Pack 2 Network Installation Package for IT Professionals and Developers
http://www.microsoft.com/downloads/details.aspx?FamilyId=049C9DBE-3B8E-4F30-8245-9E368D3CDB5A&displaylang=en

Windows XP Service Pack 2 Resources for IT Professionals
http://www.microsoft.com/technet/prodtechnol/winxppro/maintain/winxpsp2.mspx

Windows XP Service Pack 2 (SP2) Support Center
http://support.microsoft.com/default.aspx?pr=windowsxpsp2