Why is my 3D view showing up as wireframe if I keep selecting Hidden lines?
Try changing it to realistic and then back to hidden lines. Can you upload a screenshot
It can be those walls are overriden in the vg. Its not everything so not the setting in the view control bar
how do I switch it?
Go to VG and see if there is anything overriden for the walls
nothing seems to be overridden.
Is there anything else it might be?
It may be a template set to the view. Email me the file I will have a look
It has to do with the material settings. Check in the graphics tab if the surface pattern is set to transparent. You can place it on a new material and it should work.