If you have more than one operating system installed on your PC for example, you may have both Windows Vista and Windows 7 beta installed – your computer displays a menu asking you which operating system you want to load. If you don’t select an operating system within 30 seconds, it automatically loads your default operating system.
You can cut the amount of time your computer waits for your input before loading Windows Vista by going back to Msconfig and selecting the Boot tab. Where it says Timeout, change the number to a lower setting, but give yourself enough time to actually make your choice. If you only have Windows Vista installed on your machine, you don’t need to complete this step.