I want to be able to download all post-SP2 Windows Update fixes once, and then install them on different PCs without needing to download them all over again each time a PC is formatted... Is that possible somehow?
What if I need to update more than one computer?
If you have a home or small office network, you need to update each computer individually.
If you are a network administrator, go to Administrator options for information about additional update services, such as the Windows Update Catalog and Windows Server Update Services.
I tried admistrator options and selected all the updates and they were saved to a folder, but I still couldn't install them on another computer, always got an error message when I doubleclicked one of the .exe files.
Sounds like someone failed the genuine check and is trying to put an intelligent cover for it..
Seriously though, you can just go to the microsoft download section, put a filter in for Windows XP and search sorting by the date (Post Nov 2004 I believe). You have to pick and choose between XP-64bit and XP. They should work on any pc, I would find that strange if they didn't.
When you get it all together, you get this guide to slipstream it all together (updates, drivers.. whatnot).