UX Issue: Timeline Area Selection Toggle Needed?

Take a look at this... notice the blue area that has been highlighted? I am sure this "highlight an area of the timeline" feature may be useful for many workflows. However, with the ability to left-click and then select/highlight an area of the timeline is actually more troublesome for me than helpful. That highlight up there happened when I attempted to choose a point on my timeline to TESTPLAY from. SL3 ALWAYS seems to want to highlight and oftentimes just enough for my test-play to be stopped as soon as it starts. IT IS ANNOYING.

After being duped by the UX for the millionth time, I decided to take a screensnap of the event & post about it.

Now that you are aware of my dilemma, can anyone tell me how to toggle the ability to highlight areas in the timeline, such as you see in light blue on my screen snap? I want it turned off--for good preferably. Thanks!!!