What CDs are required at minimum for a no GUI install

[Rakhesh Sasidharan]

Hi,

I assume this would be an often asked question. I did a brief search of the 
archives but couldn't find anything answering it; hence I'm posting to the 
list.

I would like to try out SL 5.0 and 4.5. My intention is to have a gui-less 
install. I'd like to install SL 5.0 and then SL 4.5 on top of that as a guest. 
What would be the least number of CDs I'd have to download of either release to 
achieve something like this?

TIA,
Rakhesh