Thanks for the info. For anyone else reading this, it?? apparently a common problem with some of windows visual effects are turned on. There doesn?? appear to be a simple work around either.

I have discovered that disabling of the fading of menus in the display control panel helps. But it still doesn?? stop the wondrous yahoo widget engine causing problems. It seems any DX app that wants to run in windowed mode and use anti aliasing is stuck with the issue.

There is some light at the end of the tunnel. Apparently some of the top end (read ridiculously expensive) graphics cards do the fade effects in hardware and so they don't suffer from this problem.

Charlie