I have installed .NET Framework 3.5 SP1 and ASP.NET MVC CTP in a Windows Server 2003 R2 box, but my ASP.NET MVC site still doesn't work on that server. I was searching the internet and IIS for a solution and I noted that I can't choose other .NET Framework version besides 2.0 for my virtual directories. I'm almost sure if I correct this I can make my site work there.
Currently the main "/" URL answers with:
Directory Listing Denied
This Virtual Directory does not allow contents to be listed.
And the "/Default.aspx" URL answers with:
Configuration Error
Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.
Parser Error Message: Section or group name 'system.web.extensions' is already defined.
Phil Haack has a pretty good writeup here
http://haacked.com/archive/2008/11/26/asp.net-mvc-on-iis-6-walkthrough.aspx