Install Windows Server 2008/2003 or Linux as guest operating system into the Windows Hyper-V server.
Make sure to create Windows Hyper-V virtual machine first. Please refer to Step by Step Guide to Create Windows Hyper-V Virtual Machine.
Windows Server 2008 Start > Programs > Administrative Tools > Hyper-V Manager.
If the virtual machine is not running, You should start it first by right click virtual machine and select start.
Right click Virtual Machine name and select Connect. The Virtual Machine Connection tool window pops up.
Select Media > DVD Driver > Insert Disk... menu item if you want to install guest operating system from .iso file.
Browse the hard driver and find the .iso file.
Just click "Enter" key after step 6. Follow the screen to install window Server 2003.
Change the install media from CD1 to CD2 by choosing Media > DVD Driver > Insert Disk... menu item. Browse the hard driver and find the correct ISO file.
Click the "Ok" button to install the second CD.

This action will install hardware driver for the virtual machine.
Specify a dedicated IP for the virtual machine. So you can access the server from outside with the IP.
So you can login to the Hyper-V server with RDP.
Now your Hyper-V server should be ready for you to use.