I am interested in doing two separate things, both primarily for aesthetic
reasons. First, and more importantly, I would like to be able to set the
visible area (e.g. A1:X150). Either, the user could not travel out of the
area or it would simply not be visible. Hiding the unwanted range is
possible seems a little over the top, but this would work fine. Is there
something better?

Second, is it possible to make it so that locked cells can not be selected
or even hightlighted.

Any help is appreciated. Thanks.