Those orange circles are the Unity Grab Handles, a Compiz plugin designed to make resizing and moving easier with touchscreens or touchpads. By default, it is triggered by a three-finger tap over the window.

In the accepted answer of this question:

How do I use Unity drag handles?

there is a very detailed guide to configure the handles. Since you just want to get rid of them, you only need to uncheck the plugin itself.