with this core.dll and dshowhelper the stuttering just got worse on my dual screen setup (dropping also). Disabling thumbnail preview doesn't help here either. Only thing, that helps is "keep mP allways on top" but that damn option steals the focus from other apps and gives it to MP the whole time, so you can not really use dual screen setup with it.
EUREKA! I have found a solution that solves the dropped frames issue for me on a dual screen setup in Windows 7. Making the display that I run MP on the primary display fixes thing completely. No need for VMR9, always on top or other workarounds. I have dragged my taskbar to the secondary display and am training my applications to load on my secondary display. I was just about to wipe Win 7 and go back to XP when I thought I would try this after noticing Windows MP and MPC also stuttered when run on the TV.