copying hard drives

[David Banning]

I am interested in copying hard drives and would like some feedback.

1. I would like a way to take peoples windows -or- unix systems and
store each on portable hard drive as a single file - so that in the
end I have a large, say 2TB drive with a number of peoples operating
system backed up - that can later be restored.  

One concern I have is that the file saved is under a certain generic
standard - I don't want to be in a situation down the road where I
need to restore, but the required software to restore is defunct.
It would be nice to have the operating system on a stick - so I
could boot into the program from a clients computer, connect a large
drive, and backup their entire drive.

2. I'd like a simple way to copy - my FreeBSD system to another
drive - a clone so to speak - which I know dd can do - but I wonder
if there is a way to do this so that clone drive can be smaller that
the original. My thinking here is that I need to experiment with
changes but can't do it on a live system - hence the copy booted
from a separate machine.