To archive or back-up?

[Larry Wanger]

Hi:

When Leopard finishes installing on my Macbook Pro I'm going to put  
it on the iMac.  I have all kinds of audio, video, docs, email and  
the like on my iMac and yet want a clean install of the new OS on the  
drive.  So, should I archive when I install or just use the disk  
utility to backup stuff and then install?  Archiving would seemingly  
be easier and would create a folder with the previous system stuff in  
it.  I wonder how I simply move things to the new install?  For  
example, do I just copy the applications folder or the entire home  
folder?  Any help is appreciated.