Is there a way to connect two PCs running Windows 7 via a wifi ad-hoc network and then use Remote Desktop from one of the PCs to the other? In addition to this the Remote Desktop host PC should still be able to connect to the internet via a separate ethernet adapter, allowing the client to use the internet via the remote host screen.
I believe that the wired and wireless networks should stay separate, with different IP segments per each network.
You should then bridge the two adapters on the PC that has the Internet access.
See How to Bridge From a Wireless to a Hard-Wired LAN.
This should enable the client PC to use the Internet connection of the other one.
I am not too clear about using Remote Desktop in this setup, so just try and see.
This should absolutely be possible. Just set the ad-hoc network on a different IP range (for example, use
192.168.2.2 as the IPs for the two computers, and set the subnet mask to
255.255.255.0). The host must be able to run a Remote Desktop server (which I believe is restricted to Pro and up), but you can have a computer connected to two networks.