If I understand you use case correctly, you are speaking about showing the "please, wait" image not on ajax request, but on regular page loading. If so, a4j:status does not help you any how here.
Seems to me you can solve it using just a pure client side code:
<h:graphicImage id="wait" value="/path/to/your/image.gif" />
P.S. Please, do not use selfRendered="true" for the region if you do not realize yet, what it is for.