Just following on from some Lifecycle-related musings.
24 months after SP2 was released, Windows 2003 SP1 will cease security update and hotfix support.
From the Lifecycle Supported Service Packs page:
Windows Server 2003 Service Pack 1 / 30-Mar-2005 / 14-Apr-2009
Windows Server 2003 Service Pack 2 / 13-Mar-2007 / Not Applicable
Support ends 24 months after the next service pack releases or at the end of the product’s support lifecycle, whichever comes first. For more information, please see the service pack support policy at http://support.microsoft.com/lifecycle/Default.aspx#Service%20Pack%20Support.
When you upgrade to SP2, it’s an excellent time to apply other updates too.
My suggestion would be to test installing everything up to this minute, using WSUS, SCCM, SMS or whatever, but if there’s one update I suggest you should apply after SP2, it’s 948496. That’s the Scalable Networking Pack disablement fix. (If you didn’t know you were using SNP under SP1, you don’t want it under SP2).