You should always install the latest version (12.2.x.x currently)
Thanks for the reply Sean,
But our first priority is to see, what can be ported to the Server OS' mentioned earlier(Newer version are bound to be supported on Server 2k8 r2 and 2k12 r2). Please advice if the above mentioned products are compatible?
You won't find anyone to give you a definitive answer. I would expect so, but why don't you install them and see since you're asking.