My understanding is that the only way to perform a "repair install" in Windows 7 is to run the install setup.exe within the Windows 7 installation you want to repair. 

This seems a little brain dead to me since usually the reason I wanted to perform the repair install was because the existing installation was so broken that I could no longer boot and use it. It seems Microsoft is saying my only option in that case is to do a clean install and then reinstall all my apps.

So I'm wondering if anyone knows of a way to perform a Windows 7 repair install ... one that preserves your existing OS settings and application installs ... on a Windows 7 partition which ***cannot be booted***.