Restoring After a Disaster
Restoring from an event such as a failed hard drive or onto a replacement computer requires a slightly different approach. If you're restoring to the same computer (or a replacement computer of the same model), you can select "Restore system from backup" from the Utilities menu after booting from the Mac OS X Leopard install DVD.
The installer will search for available Time Machine backups on connected hard drives (network hard drives can be selected using a "Connect to Remote Disk" button). When you select your hard drive from the list, you will be able to choose which backup to use.
Being able to select from previous backups in addition to the most recent is helpful if you suspect recently installed software (or other system modifications) are causing problems with your Mac. Backups are listed by date and time and include a Mac OS X version of the backup (which is good if you experienced issues after an upgrade). After selecting a backup (there is no preview feature), you can select which hard drive or partition to restore to. Restoring will replace the contents of the target drive with the contents of the backup.
If you're not restoring to the same computer or Mac model, you should use Migration Assistant to restore. Although most Macs have similar hardware, there may be differences in the system and driver files installed as part of Mac OS X. Performing an install rather than a backup ensures that the appropriate files are installed. This is also the option you would take if you choose to exclude system files from your backup.
When used with Migration Assistant, you install Mac OS X normally and then choose a Time Machine backup as a source for migrating your settings, files, and user accounts. The process is virtually identical to what you would do to transfer settings and data to a new Mac from a fully functioning Mac that is being replaced. Again, you will have the option of choosing from among the available backups on the drive.