Go to Start then Run
Type ‘Regedit’ then click ‘Ok’
Find “HKEY_CURRENT_USER\Control Panel\Desktop\”
Select “MenuShowDelay”
Right click and select “Modify’
Reduce the number to around “100″
This is the delay time before a menu is opened. You can set it to “0″ but it can make windows really hard to use as menus will open if you just look at them – well move your mouse over them anyway.

Follow this for more tweaks:

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