Today for one of our branches I have to install SharePoint 2007 on Windows 2008 R2. Before you start you have to remember a few things:
1. If you plan to use SQL server 2005 you need at last service pack 3.
2. SharePoint installation files must contain service pack 2. You can’t install without it.
3. If you installed before Office 2010 you will get error during configuration step 2: Exception: Microsoft.SharePoint.Upgrade.SPUpgradeException: One or more types failed to load
I don’t know why but you have to remove it. When you do this Wizard will be able to create configuration database.