Security updates are available on ISO-9660 CD image files from the Microsoft Download Center
http://support.microsoft.com/kb/913086
You can also download individual updates from the Catalog and save to be installed later.
http://catalog.update.microsoft.com/v7/site/Home.aspx
Click Add button for each update you want to download. Once you have what you want, Click the “Go To Download Basket” link. Type in or browse to the location where you want the updates saved to and then Click the “Download Now” button.
Once downloaded, you can then burn them to CD.
How to download updates and drivers from the Windows Update Catalog or from the Microsoft Update Catalog
http://support.microsoft.com/kb/323166
Microsoft Security Bulletins - current listing