Monitor refresh rate problem!!!

I am using Windows 7 32-bit OS.I have NVIDIA 9500 GT video card installed on my pc.I have set my monitor's refresh rate to 75 hz,cuz at lower rate(65 hz or lower) monitor screen looks like wobbling.Now i have a problem that whenever i start a full screen application or game,screen's refresh rate automatically changes to 60 hz.After exiting the application it returns to 75 hz.Is there any way to fix this,so i can keep it to 75 Hz even when any game is launched.Some games provides in game refresh rate change option but mostly don't.Any help will be appreciated.
Thanks!