virtualbox.org

I've been trying to figure this out but haven't had luck yet.

I have two nics that I want to connect to two separate networks.

I want my desktop (windows 7) to connect to my ethernet connection, and my virtual PC to connect to my wireless card.

I don't want my desktop to be going out on the wireless, and I don't want my virtual going out on the wire.

How can I set this up?

If the wifi is USB, put the device in the VM directly. If it isn't, a bit of tough luck, the Host must make the wifi connection with the access point. You can disable the communication protocols (IPv4 and IPv6) so it doesn't get anything from the wireless, so the VM can use the connection. As long as the bridged connection is on the wireless interface, the wired is OK.

Can't you do it the other way around? Let the Host stay on wifi and let the Guest use the wire? For the wire on the Host, you still need to make sure that the other systems can't reach it, so either do the same as above for the wifi, disabling the protocols, or set a completely different IP address on it.