Some editions (see note below) of Vista include Complete PC backup utility. The Complete PC Backup in Vista allows you to backup your files or the whole system drive to a network drive, a removable drive or another partition not in use by the system. The image below is the screenshot of Windows Complete Backup in Vista Ultimate edition:

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Note: Included in Business, Ultimate and Enterprise editions of Windows Vista.
All editions of Windows 7 includes a backup utility, however the Starter, Home Basic and Home Premium editions do not include backing up to a network drive.

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Reminder: Always remember to insert the last backup disk instead of the first backup disk when restoring to your backup from removable disc. It’s not First In, First Out (FIFO) but Last Out, First In (LOFI).
If you have a Seagate or Maxtor hard-drive, you can take advantage of the OEM edition of Acronis True Image backup utility. You can download DiscWizard at Seagate website.
For users who prefer paying for a Windows backup software, which includes support and extra features in backing up your computer (additional features include exploring the backup, drive cleanser, backup scheduler and Try&Decide), I highly recommend using Acronis True Image or Paragon’s System Backup 2010.
Whatever method you will use, it is always recommended to have a complete backup of the whole drive in addition to a system drive backup. This allows you to recover to your previous working system state in 10 to 30 minutes!
Note: The time restoring a backup depends on the file types you will be restoring or backing-up. If you have plenty of .mov, .mpeg, .wav, .mp3 or other media files, the backup and restore may take longer.