Susan Bradley (who I respect highly) states in this article that there is no way to uninstall Flash Player.
Sorry Ms. Susan, but that is not totally correct.
There is a Flash Player Uninstaller program on this Adobe Labs web page. You need to scroll down and look for the title “Uninstallation”; below this title you will find a download link titled “Download the Flash Player beta uninstaller for Windows”.
For a few years now I get the newest (beta-!) flash players from this page. Some don’t install over an older version and give a message to run the uninstaller; that is how I discovered it.
I can’t test this but I would assume that after running the uninstaller future updates would install the correct flash player – if MS has gotten their act together.