Try right clicking on the scene area and looking to see if you have "SreeD" or "OpenGL" checked.  Which ever one you have with a checkmark next to it, try the other one to see if that helps.

Also, do you have SR3 installed?

Try downloading new video drivers.

Did you install any programs during the time when you started to notice the problems? If so, try uninstalling them and see if that helps.

Apprently Quick Time can cause problems with Poser 6 too.  Though I haven't had a problem with it. But if try uninstalling it and see if it helps you.

Go into your Windows User  folder and delete the Poser cache.

Have you done virus and adware scans? Those things can cause lots of grief!!!  (the virus and adware, not the scans :) )

Those are the only suggestions that I can think of. Maybe someone else will have some others.

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi