Managing the hard drive. Western Digital Studio 2TB

I am backing up my iMac 2.16GHz Intel core Duo prior to a complet erase and and re-install. I also have a seperate external LaCie hard drive dedicated to Time Machine back ups.  The internal Drive is virtually full 229GB used of a 250BG.

I want to start fresh moving up to Lion/Mountain Lion.

My idea was simply to copy my hard Drive accross to the WDS (belts and braces) but was taken with the smartware. and is now backing up.

I have several questions

  1. I have several Identity / users on my machine. I take it each of those is backed up seperately?

  2. Having backed everything up I plan to use the WDS to be a secondary incremental back up using the smartware but want to use about half the capacity to keep my pictures and music libraries there for access by iTunes and iPhoto. Do I somehow partition the WDS or simply set a limit to the number of Back Up as per the instructions and simply open up new folders/libraies in the WDS?

Any problems with this? is it as simp0le as it appears?

What is WDS?

I will rather use Time Machine