You’re doing a fresh installation of Windows XP. Is there a way to download service packs and updates so that you don’t have to go through a long, long update process before you can use your computer? Yes. In fact, this method is especially useful if the new computer has only a dial-up connection but you have access to a high-speed computer elsewhere.
The Windows Update Catalog allows you to search for specific updates depending on the version of Windows you currently have installed. If you only have the original release of Windows XP, choose Windows XP RTM (Home Edition) or Windows XP Professional RTM from the list. If you have downloaded and installed Service Pack 2 separately, choose the SP2 option for your version of Windows. (If you’re looking for drivers, click Find driver updates for hardware devices and search by category.)

After you click Search, you’ll see a list of available downloads, arranged by category: Critical Updates and Service Packs, Multi-Language Features, Recommended Updates, and so on. Click the Add button for an individual update to make it part of your download basket. Click the Download Now button to fetch the files you’ve tagged. You can then burn the files to CD or other media to make them available for installation.
Pretty neat. Comes in handy for me (I’m about to do a format-install with my SP1 disk). I wonder why that is only on the V4 site and not the current V5 update site?