So I went ahead and migrated my vista install from a bigger hard drive to a smaller hard drive.

/dev/sda = 160gb hard drive
/dev/sda1 = 60gb vista partition

/dev/sdb = 120gb hard drive

Ran "dd if=/dev/sda of=/dev/sdb bs=32768" and after 45 minutes or so gave me a "disk full" error. Removed my 160gb drive and rebooted using just my new 120gb drive. Vista booted up fine and I used Vista's disk management tool to "expand" the 60gb partition to the full 120gb.

Every thing's working fine, except that I had to re-activate my vista install.

Thanks again for the guide.