External Hard drive questions

we just bought an external hard drive to be used as the archive media to
store images offsite. This is to replace archiving each image to dvd and
storing them offsite. so this poses the following questions:

1. A number of our images are greater than 4gb. Given the limitations of
certian file systems (namely, fat32) what should the format of this
external drive be?
2. Is it possible to send an image directly to the external usb hard drive
using the zen7 boot cd? Is it possible to restore an image from the
external hard drive using the boot cd?

given those questions, what file system would have to be used in order to
view the images in windows, while allowing the imaging engine to write to
or read from the hard drive, and satisfy the inherent 4gb file size
limitation? assuming its even possible.
thanks.