The minimize and maximize window animations that first debuted in Windows Vista were an improvement over the effect in Windows XP. While this new effect had a high “cool factor” (especially with the slow motion key) it eventually wore off and created an unnecessary delay when switching between windows.  

Disabling the effect will instantly make your computer feel more responsive and faster. Give it a try and see for yourself:

1. Click on the Start Button and type in SystemPropertiesPerformance and hit Enter.
2. On the Visual Effects tab locate and remove the check from Animate windows when minimizing and maximizing.
3. Click OK.