Today after leave this blog silent for a while, i find some problem to write in this blog, i borrow my friend's notebook and she ask me to help make her Windows Vista can use flip-3d(switching window like alt+tab(2nd picture), but more beautiful interface with preview), now i'm working on her Windows so if you have a same problem and want to enable flip-3d, we'll do it together.
We'll do it in regedit, open run box by press window+r keys on keyboard, type "regedit" (without quotes), in Register Editor find this path, HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\DWM, if you don't have DWM like me, see above picture, create it by right click Windows folder in tree on left side panel choose New->Key, named it to DWM, then click DWM and right click on any area in right panel, choose New->DWORD (32 bit) Value, named new key to DisallowFlip3d, double click it to set value, type 1 in Data Value field to disable flip-3d, or set DisallowFlip3d to 0 to enable.
Restart your current Windows session by logout and re-login or restart Windows to make flip-3d take effect. For now you should can use flip 3d, to use it press [window key + tab] or [window key + arrow] to switch window forward or backward as you want. If you have a problem to do this or it's not work for you or you have some tricks on this topic you can tell others people by leave a comment here, if it's a problem i'll try to solve for you.