This interesting question came up in a discussion recently. The answer is no, but you have to think very carefully before coming up with a definite answer.
Understandly, you need to enable DHCP on virtual networks to simulate the environment you're configuring, and don't want to run a seperate DHCP server as a VM or elsewhere on the network. 99 times out of 100, you would only turn on the Virtual Server DHCP server on a "virtual" network (as opposed to "physical" virtual network - ie a virtual network bound to a physical host adapter). Yes, it gets confusing trying to describe this!
However, the Virtual Server admin interface also allows you to enable the DHCP server on virtual networks bound to physical host adapters too. This takes a little head scratching to work out why you would want to do this, but it is possible - almost defeats the point. Fortunately (and by design), the Virtual Server DHCP server is smart enough not to allocate IP addresses to anything which is not a virtual machine, regardless of which network adapter (physical or virtual) the DHCP server is turned on for.
I had to try this one out just to be sure, but this definitely what you'll see if you try for yourself :-)