VMware vs Microsoft Virtual PC 2007 - Which is best for testing viruses?

I want to help the comunity by testing virus files on a virtual PC so it won’t infect me so I was wondering witch Virtual PC is the best and if it can stay in the virtual PC and not infect the host.

~Donovansrb10

VMWare has a lot of background working services and drivers… it’s a resource hog. But it works very good and it’s stable and solid.
Other option for virtualization is VirtualBox.

The host pc is not completely isolated from the guest one, so take care.

I prefer VirtualPC because of drag and drop functionality between host and client.
With VirtualBox and VMWare i have to transfer files from one to another by different means which aren’t as convenient as drag and drop.

Ok, but can you help me why I get this error when I start it:

Title: Virtual PC
Body: Virtual PC has detected an invalid or missing Product ID.

A valid Product ID is required to operate Virtual PC. Please re-run the Virtual PC installer and enter a valid Product ID when requested.