seems like I opened a big can of worms with this question didnt I...........

I always thought MS was complicated but this takes the biscuit.........

Thanks to all who have offered their advice and I will endeavour to solve my querrie in due course.........

regards from creakin.............

I think the question was a more general one: where does the "automatic updates" function (that existed prior to SP2) put the files it downloads? So that one can - say - copy them to another computer without having to download them again?
The downloaded files are the very same patches that are made available through the Windows Update site; and just like those, they are presented for download/downloaded only if applicable to the specific system (i.e. the operating system version matches and the patch is not yet installed). Provided that these specifics are the same, the patches can be applied to multiple systems.

They are the same packages as those delivered "manually" via Windows Update. Automatic updates are just another way of delivering the same stuff without having the user to browse to the WU site.
It's convenient, but I wouldn't let it blindly install the patches, not even download them; it's enough to get notified of their availability. In this I agree with you.
That said, both Windows Update and Automatic updates scan your PC and determine what's needed and what's not. But this is done - as far as I know and unless I'm mistaken - on a "patch needed/patch not needed" basis, which means that the single patches are not repackaged depending on the specific system configuration.
If - say - MS releases a patch that replaces 10 original system files, the patch is completely downloaded if WU or AU detect that it's not already installed as a whole on a specific system. This means that the patch is downloaded in its entirety even if on the specific system some of the files it contains are already up to date. So it can be safely copied and installed on any other system that needs it without downloading it again.
Maybe that with AU the various patches are downloaded in a single package, and that's why size differs from system to system?

hi to everyone who has been reading my string...........

I just thought I'd update everyone.......

I was having other problems on my pc so I decided to do a clean install. I then downloaded winxp sp2 (266mb download) and installed it - up to now everything is running ok  . I've not put fs9 back on yet but will do so shortly. I'll report back any problems I encounter...........

creakin chris

I love SP2, it was particularly effective in the popup blocking department. Properly configured it will make your machine a very useable one. I installed it before and it buggered up my PC but on a fresh XP install it worked like a dream! BTW, make sure you download the MS antispyware tool, it is the best!