Norton Ghost "Backup My Computer"

Running Norton Ghost 15 SP1 on dual-boot Windows 7 32-bit/ 64-bit HP computer.

 

As illustrated below:

 

SYSTEM drive has the boot manager files

Drive C: contains Win7 32-bit OS and Ghost 15 SP1

Drive E: 2nd HD contains Win7 64-bit OS and becomes Drive C when booted up into Win7 64-bit OS

 

 

Goal: To maintain backups of both  Disk 1 and Disk 2 on external USB drive so in case of either drive failing, can restore only to that failed drive and then reboot up successfully into both Win7 OSs.

 

Confusions:

 

1) I'm to use the Define Backup Wizard and not the Copy Drive Wizard, right?

 

2) In Define Backup Wizard, after choosing, Backup My Computer, is the goal to create one  *.v2i image per partition?

 

3) If so, when I try to select just the SYSTEM partition, I next get a Related Drives screen which suggests adding both the C Drive and the E Drive to this one Recovery Point Set. There's a warning that unless I follow this recommendation, my recovery may fail. Same thing happens if I choose to only backup the E Drive. If I make just one Recovery Set that includes partitions that span two drives, will I still be able to successfully restore just one of the two HDs should either one fail, or would this force me to restore to both drives?