WPF rendering freeze
Am i right ? Would it be more a WPF problem, or a video driver problem ? or even DirectX ? Are there some parameters I can tune around this ?
This sounds like a driver issue. I would start with seeing if there are driver updates. The best option might just be to disable hardware acceleration altogether, as WPF (on XP especially) really relies on the graphics drivers.
Visual Studio 2010 sp1 disabled hardware acceleration for itself on XP for exactly this reason...