If you have a Mac that has been equipped with Windows in a BootCamp partition, follow the instructions below to restart in Mac OS X.
1. The BootCamp control panel is available in the system tray in Windows, and appears as a black diamond.
2. Right-click on this icon, and select 'Restart in Mac OS X' from the menu that appears. Remember that this changes the default startup volume setting, and the machine will continue to boot to the Mac OS unless another option is chosen at startup or the setting is changed.