Vista - Maximum 30 fps in vista, help me!

I am using gpu nVidia Geforce 8400m g in my laptop. my laptop was just fine before installing the 179.28 driver, except for gaming.

However, my computer starts act strangely after 179.28 driver installed. When I closing, opening, maximising or minimising my window(I am using aero with fading effect), I can see it lags. These are not the worst yet! My certain games which can run finely before, also lags. Actually, its fps stuck on 30 fps, no more than or less than that!

i have heard about vertical syn is causing this problem, but i do not know how to disable it. i would much more appreciate if anyone can help me.
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sorry for my broken English

you have come to the right place and first thing i would ask you to do is to right click your desktop (anywhere as long as its not on an icon) and go to Nvidia control panel. this will bring up a window saying advanced or standard, I need you to click advanced for me, when it opens, you should get a few options come up, on the left, theres a + next to 3d settings, and in there is an option saying manage 3d settings, click this and you will get lots of options, scroll down to the bottom of this list and you will see vertical sync, set this to force off and this will solve the 30fps in games.
what would also contribute to the 30fps without disabling vertical monitor syncing is the Hz that your monitor is displayed at, my monitor is displayed at 60Hz so my fps in game is 60fps if vms is enabled, right click your desktop and click on personalise, click on display settings, and click on advanced in that box, this will bring up the adaptor information, click on the monitor tab and change the refresh rate to 60hz(this will only be available if your monitor is at its native resolution, which in your case is 1280x800), but this should increase your framerate exponentially with vertical monitor syncing enabled