I have a Western Digital 74GB Raptor as C:, with Windows 7 Professional Installed - TechNet Subscription. I use Acronis True Image Home to do backups of the drive.
Restored a backup to a Maxtor 640GB HD, which is my 4th HD used for storage. Maxtor was formatted prior to backup restore.
Upon restore completion, rebooted, entered "set up", turned off HDs 1, 2, & 3 and booted to HD4. Windows 7 ran CHKDSK, first time I've ever seen that, booted OK and Windows was activated and "good to go".
I'm not sure how/if this relates to the topic, other than I was able to boot to Windows 7 on a HD other than the one it was installed on originally.
I thank the OP for this topic - now I know how to replace C:\ with a new HD - thanks toneefresh.