firefox popping up

Hi, I use Firefox as my default browser and every time I click a link or even when I was signing in here a window will popup asking me to update my video player because it's out dated. This is coming from Firefox and it's maddening. There is not one place I can go on the internet that it's not there, it popped up when I clicked to log in here and it's no little window. It's in the background now. I decided to do the update to get rid of it and here is what I got:"setup. exe" by "tuguu Israel Ltd....Not doing it! Don't know what that is! I guess I'm stuck with this thing.
Tryed to put a screen shot on here but don't see any option for "screenshot"..Can't drag and drop it either! I select "insert image" it asks for the URL.

barb