Thank you for your help.
To provide more information:
I have now discovered that there is a long delay (not freezing) when opening "Advanced Tweaks" and after I close the main settings.
The delays (or freezing) occur when I close any windows, including the settings window.
I don't use the Quick Launch dock because I can't hide it (sliding it off the screen). I don't like seeing it, and yes, there is no delay on the Quick Launch dock.
There is no delay (or freezing) on empty tabs (I tested with only one dock). Currently, I am using four docks. Do you see my settings?
Thanks again!
Laercio