Startup 9.2.1 repairs problems that may occur when Mac OS 9.1 and Mac OS X are on the same partition and a version earlier than Startup 9.2 has been used. The Utilities folder on the Mac OS X CD contains Startup Disk version 9.2, the control panel you use to select the startup disk for your computer. You need to use this version of Startup Disk to select a Mac OS X disk as your startup disk. Important If you start Classic after installing Mac OS X, Classic installs this version of Startup Disk in the Mac OS 9.1 System Folder it uses.
Mac OS Classic,
Mac OS X 10.0