Flash Player Causing me grief

Since downloading the latest Flash Player, my computer does not work right.  Screen saver does not deploy, when I am playing games, computer keeps pausing and going back to the desktop (this is constant), I have to keep clicking resume.  Some web sites are not working (i.e., e-bay) when I need to view a video that runs with flash player I get an error message that says I do not have Flash Player downloaded.