What is slip streaming? It’s adding the service pack files to the original media so that when you do the initial install, you are installing the service pack too, rather than doing two installs.
Martin Kearn has a nice article on this (http://blogs.msdn.com/martinkearn/archive/2008/01/14/how-to-create-a-slipstream-installation-for-moss-with-sp1.aspx ). The only things I would add are 1) that you can use the extract command on the two executables to extract the files directly to the Updates folder, 2) when you do this, you end up with 31 files in the Updates folder – 5 from WSS SP1, 25 from MOSS SP1, and 1 Readme that was there already.
So if you have copied your MOSS RTM install media to e:\installs\MOSS2007\, you will have e:\installs\MOSS2007\Updates, and you can specify that directory when you run the SP1 exes:
<long name of WSS SP1 exe> /extract: e:\installs\MOSS2007\Updates
<long name of MOSS SP1 exe> /extract: e:\installs\MOSS2007\Updates
I did this with the 32-bit version. I suppose the number of files in each service pack could differ in the 64 bit version.