Re: Application Server Upgrade from windows 2003 to latest supported version
IMO you should think to upgrade your PPM version to at least 9.3x version. Because 9.1x committed support ended on Oct. 31st 2015.
Last version, which is 9.40 supports the below Microsoft platforms:
Microsoft Windows Server 2008, SPs 1 through 2, Standard, Enterprise, and Datacenter Edition (64-bit) Microsoft Windows Server, 2008 R2, Standard and Enterprise Edition (64-bit) Microsoft Windows Server, 2012 R2, Standard and Enterprise Edition (64-bit)
You have to upgrade PPM step by step from 9.12 ==> (9.14 if documentum used) ==> 9.20 ==> 9.30 ==> 9.40. You can refer to "Upgrade Guide"s for each version seperately, which can be downloaded from HPE Support web site.