Once the installation is complete, the installer will continue to the Quicktime Setup Assistant. The next series of windows will help you configure Quicktime for optimal use on your system. Click the "Next" button in the first window to begin.
The next window will allow you to set your connection speed. Use the drop-down menu to select the closest possible speed to your Internet connection. Below this drop-down menu is a check-box that will enable multiple simultaneous Quicktime streams. Leaving this box unchecked should have no effect on most streams, and you should only enable this feature if you have a suitably fast Internet connection.
Click "Next" to proceed.