T-13 is when windows finishes the registry and runs any scripts in svcpack.inf. Windows SBS 2K3 hangs for about 20 mins at T-13, and this is normal. During this time you propably don't have disk activity, but your processor will be under heavy usage, as rebuilding the registry and other thing that happen here require a lot of power. If you have QFECheck on your CD, this is when it runs, along with SFC, to ensure that all updated file are legit, and the newer version gets kept if there are multiple versions of the same file. If you integrateded a LOT of updates then i would expect this to take 5-10 mins, but that is far too much.