Often I hear people complain about the Microsoft Hyper-V manager, for instance: copying files from the host to virtual machine by using the clipboard is not possible, this is because the Hyper-V manager is not intended to be used like VMWare workstation or player.
Only use the Hyper-V manager to “manage” virtual machines eg start, stop, copy, clone, add or remove hardware etc.
When you want to connect to the desktop of the virtual machine, use Remote Desktop.With remote desktop it is possible to copy files from the host to the Hyper-V virtual machine by using CTRL-C and CTRL-V (using the clipboard). In windows 8 the remote desktop experience is really improved, so take a look at it.
TIP: You can still use free programs like Microsoft Remote Desktop Manager v2.2 to manage multiple rdp connections, but the “metro” windows 8 RDP app is pretty good.