Hi, I currently use a notebook with Intel 7i with many VMs as my pentest lab. I find the mobility and flexibility of working with a notebook alot better. As I can use is at various locations.
For linux VMs eg. Backtrack. I would make use of SSH and therefore can reduce the memory usage of the Backtrack image.

I group the questions into PPT.

1. People
Know the various groups of users of the system and their roles.
E.g. Sys admins,Monitoring team

2. People
Backup processes,patch processes Incident response processes

3. Technologies
Have a system architecture diagram and data flow diagram to show how the various machines communicate with one another.

Hi, I frame my learning process into 3 main parts:
1. Host
Learn to be comfortable using and configuring both Windows based and Linux based OSes.
I have a laptop that I dual boot to have both windows and Backtrack. By forcing myself to use Backtrack(linux) I was able to learn many linux commands fast.

2. Applications
Learn to built your own website with any language E.g. PHP
Learn to configure web application servers E.g. Apache or IIS
Learn to configure databases E.g. MySQL

3. Networks
Read up on TCP/IP and understand how packets flow and formed in the networks.
A very good book to start reading is TCP/IP Illustrated. However, do note that it is very dry.
Make use of wireshark to collect network traffic while you start surfing the web. By looking at the packets collected and cross reference to TCP/IP Illustrated book you can learn alot about networks.
Last but not least google is your friend. God Bless.