Damn this old, but I found an article explaining how to achieve that. Heres the sauce.
First of all the standard warning, that this will include changing a registry-entry which, when done wrong, may be able to brick Windows. So be careful and pay attention.
- First open the registry editor: Press "Windows + R" and type in
regedit, then hit ok. You should be prompted for admnistrative rights from the UAC, hit yes on that and continue
- In the new window find your way to
HKEY_CURRENT_USER\Control Panel\Desktop (you can copy & paste this path in the box above, easier then to go through everything yourself)
- Now select the entry called
MenuShowDelay in the right pane, right-click it and modify the value from (default)
400 to anything you'd like. I would suggest changing it to
Congratulations, you have successfully changed the animation speed in Windows!
Please note, that the changes won't take effect until you have rebooted your machine