So, I recall having to purchase Norton Ghost to create an image and then to reapply that image to a new hard disk.  For a laptop this would have been a great challenge.  My steps would have looked something like the following:

• Purchase Norton Ghost
• Copy the entire existing hard drive to the new hard drive
  • This would have entailed getting an enclosure for my new laptop hard drive and copying directly to that
• Swap the hard drives and then reactivate Vista

However, since I didn't feel like getting an enclosure that would fit my new laptop hard drive, I did something different.

• Use Vista's built in capability to backup my entire computer (creates a VHD of your machine) to a USB hard drive I had
• Swap the hard drive in my laptop with the new (unformatted and larger) hard drive
• Boot to the Vista CD and choose to restore my computer with the USB drive plugged in
• Wait for about 20 minutes (with a 50 GB backup vhd)
• Come back to the computer and find that it booted up successfully with an exact image of my old hard drive

The really cool part is that I remember in the old days that after this happened, Windows didn't recognize the additional space on the primary partition.  We used to have to get repartitioning software to expand the primary partition.  However, in Vista, I saw the unclaimed space on the primary partition and simply expanded the primary partition right in the disk manager!  Now, with only Vista and a USB hard drive, I was able to restore an image of my machine to a larger disk without having to rebuild, etc!