Windows Home Server is
not DLNA compliant.
As for Nero MediaHome 4, I think you will have to consult with
Nero on that. An extremely brief review of their web site suggests that it's capable of running on Windows Home Server, but I don't know enough about the software to say how hard it would be to configure it for use in the WHS environment (or if it would even be possible).
I'm not on the WHS team, I just post a lot. :)