Please note that these instructions are for informational purposes and standard procedures apply before following these steps such as practice on non-production environments, backup of site and information, checking for updates for files at Microsoft.

I gathered these steps from several places and thought having the consolidated information was a good idea.

Steps for the common scenario of upgrading from WSS SP1 to SP2 ...

1. First install WSS SP2, search and install Microsoft download WSS2003SP2-KB887624-FullFile-ENU.exe

2. Install Language Pack (only if installed), search and install microsoft download WSS2003SP2TPK-KB887624-FullFile-ENU.exe

3. Tell IIS to set the ASP runtime to 2.0 on the root and all virtuals below by running ...
"%windir%\Microsoft.NET\Framework\v2.0.<ASP.NET 2.0 RTM Version>\aspnet_regiis.exe -s /w3svc/<identifier>/root/"

Note that %windir% is the directory where windows is installed, <ASP.NET 2.0 RTM Version> is the version of the .net runtime and <identifier> is the IIS id in the IIS metabase where your WSS is found

4. Have Sharepoint do the upgrade to all sites to run under .net 2.0  ...
"stsadm.exe –o upgrade –forceupgrade –url http://URLOftheVirtualServer"

5. Create a stsadm.exe.config file where stsadm.exe is located like below:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <startup>
    <supportedRuntime version="v2.0.50727" />  <!-- update the version # once .Net v2.0 is released -->
    <supportedRuntime version="v1.1.4322" />  <!-- this is the version number for .Net v1.1 -->
  </startup>
</configuration>

6. The rest just like in vs2003 … in VS2005 - compile, create all the wppack parts, make a cab with stuff in it, install