I have never really felt comfortable with the Ubuntu Linux OS
you're never going to be comfortable using something if you use it once, then don't touch it for several years
Will an Armory Ubuntu wallet still be recognized on a Armory Windows setup?
yes
Additionally, do my private keys on my Offline Ubuntu PC stay where they are at? Or do I need to move them to a separate offline Windows PC?
keys can stay on Ubuntu offline machine.
In short, is it a good or bad idea to migrate from Ubuntu over to Windows?
it'll work, but you're giving up your privacy, who Microsoft will sell to anyone they like