Desktop Picture Change Problem

[The Past]

I searched, but apologies in advance if I searched bad. It has been a few sleepless nights.

10.5.x does not allow me to access files in my pictures folder to set as desktop background. I understand it has something to with also having Aperture installed.

Is anyone aware of a fix or a workaround for this? I am unable to change desktop image with Aperture installed.

Thanks.