[2snakes]

Navigate to Computer\HKEY_CURRENT_USER\Control Panel\Desktop. In the right-hand pane, look for "MenuShowDelay" Change to 0 delay.

[solardev]

Doesn't that change the hover-over pop-up speed, like when you're selecting a sub menu item in a tree? Does it also affect the initial click?

I used to do that on every Windows installation. Then I eventually just gave up on Windows, lol.