Hi Fred, Virtual PC is just one of the many useful programs that I have first learned about from The Langa List. ( http://www.google.com/search?as_q=virtual+pc&as_sitesearch=langa.com )
I use it to try out software that I am not sure I want to permanently install, rather than run different OS. After a while, each Virtual Machine gets cluttered with the garbage created by installing and uninstalling software, and it’s great to be able to just wipe it out and start with a clean version.
Creating a new Virtual Machine is relatively quick, what takes the time is installing the OS (XPPro in my case). So I experimented to find a better way. It seems to be surprisingly simple.
First create a new Virtual Machine and give it a name. Then install the operating system of your choice. Run any service packs and patches, load any utilities etc and customize it any way you want. Then turn off the new Virtual Machine and close the VPC console.
Using the host PC find the .vhd file you have just created, which will be called whatever you named the Virtual Machine followed by the words "Hard Disk". If you have difficulty you can search for *.vhd. Copy this hard disk.vhd file to some convenient location for safe keeping, a separate partition or drive than the one the Virtual Machine is on obviously makes sense. Then to avoid confusion in future rename this copy something like BasicOS_VM
When you need to set up a new Virtual Machine just create one using the "New" box in the VPC console and name it whatever you want, say NextVM as an example. This will set up a new NextVM Hard Disk.vhd file. Find that, and make sure you know exactly what it is called and where it is located. Then delete it.
Copy your BasicOS_VM.vhd file from wherever you stored it to the location of the file you have just deleted and rename it with the name of the deleted file. Keeping to our example this would be NextVM Hard Disk Then start "NextVM" or whatever you called it from the VPC console and you should find you have a pre-installed OS ready to go.