Updating windows Vista (XP and 7 too)

Run a Windows SUS server so that all the updates are done from the local network. That should be much quicker.

If you were dealing with the same hardware all the time you could just make a Ghost image of a fully updated system, but that's not so easy with a mixture of hardware.

No, it is different hardware all the time. Can you provide a link telling me how to set up such a server, or provide that information in detail here?

Oh yes, I should add, this would need to be set up on a windows 7 machine, not a machine running any of the Microsoft server line of operating systems.

How to Slipstream Service Packs -- by creating a slipstream installation media you can add the latest service packs to the actual install media so all of the updates will be installed as part of the installation process and then all that is needed is to update with the releases since the last service pack !

This feature has several major flaws. First, doing this to a factory restore image would be impractical/impossible (and that's what i use most of the time, the customers factory restore image.) Not to mention I would need to do this to every computer that came in, as each computer would have a different restore image. It assumes I know every update there is available, and how to go about getting them without using windows update to download it/install it. However having these files locally and knowing which packs can be installed together without a reboot MAY speed this process up.

Eight hours? How fast is your internet connection? Windows updates usually only take a couple of hours... maybe 3 or 4 at the most. To cut some time, you can download the network distributions of service packs to a local machine and then run them on the repaired PC. If you install all service packs first, this should drastically reduce the amount of time you need to spend doing updates. It would be nice if you could install SP 2 for Vista without installing SP 1, but alas, you can't. Having the files downloaded locally should help a lot, however.

20 meg service

Direct fiber connection to the best ISP in the city. And yes, I get 20 megs all the time. It is even burst able, so if I was downloading a 2 meg update, it would come in at about 100 megs.
The issue is, they stall. Even a small update will sit at 64% (or whatever number) for several minuets before continue.
The issue is not my ISP, it is microsoft.
Now, where do I get just SP1 and SP2? that MAY be ideal, I am unsure, but worth a try.