This links to the article I wrote.
Here's an exerpt.
The rest at http://bbqsrc.org/?q=node/20Introduction
This HOWTO will be using Puppy Linux to setup a testing environment for Puppy inside But all of this HOWTO can be used for any operating system. I will have two options for most things: generic and Puppy way. You will probably need root privilages for the installation of the programs, but the virtualisation itself requires no root access (Puppy users need not even read that )
Be warned, a Pentium 2 can not run this, and a Pentium 3 may struggle. Recommended RAM is at least 256mb, and even then it will run quite sluggish.
What we need:
Qemu >=0.9 (Puppy Linux download - [link])
SDL (Puppy Linux download - [link])
A base operating system (eg. Puppy Linux)
The CD or CD image of the operating system to be tested
[optional] Kqemu - speeds up virtual system (Puppy Linux download - [link])