Thread:Project:Support desk/Migration of 1.12 on Linux to Windows 2008

I'm new to MediaWiki, and I've been tasked with moving an aging 1.12 heavily customized MediaWiki farm from Linux to our VMWare installation, which is all Win2k8 R2, and if possible use IIS7. I've looked through the relevant installation, migration and server move documentation for MediaWiki, but I could really use some advice on how to generally approach this. Is it better to upgrade the existing installation before I move it? Install a new stack of everything (PHP, MYSql, MediaWiki) on Windows and migrate individual bits as needed? Is there an existing discussion, maybe (I haven't found yet one searching my own)? Thanks!