Linux

I know that this is probably a "religion" issue but we are looking to move Postgres to a Linux server.  We currently have a Windows 2008 R2 active directory and all of the other servers are virtualized via VMWare ESXi.  One of the reasons is that we want to use a 64 bit Postgres server and the UUID processing contrib module does not provide a 64 bit version for Windows.  I would also assume that the database when properly tuned will probably run faster in a *inx environment.

What and why should I look at certain distributions?  It appears from what I read, Ubanta is a good desktop but not a server.

Best Regards