Thank you for your post.
Which video monitor and driver are you using?
Have you downloaded the trial version of FileMaker Pro 10? If so, does the same problem exist?
One of my machines is a Dell Dimension running Windows XP sp3, and I do not have the refresh problem.
Any information you can provide may be helpful. I'll make sure it is forwarded to the appropriate people in our Development and Software Quality Assurance (Testing) teams.