Chandima Kulathilake has a good post on his blog about Service Pack 2 for SharePoint, which includes the binaries install order. Here’s an excerpt from http://www.chandima.net/Blog/archive/2008/10/29/sharepoint-service-pack-2-is-coming-are-you-ready.aspx:
Binaries install order
1. The 2007 Microsoft Office Servers Service Pack 1
2. The Windows SharePoint Services Infrastructure Update x86 x64
3. The Microsoft Office Servers Infrastructure Update x86 x64
4. KB 953397: Excel Server Security Update x86 x64
5. KB 955586: Document Lifecycle Workflow Update
6. August Cumulative Update for Windows SharePoint Services 3.0 (Global)
7. August Cumulative Update for Microsoft Office Servers
Note: As of this posting, the latest Cumulative Update was released on June 30, 2009. Here’s the URL: http://support.microsoft.com/kb/971538