Connecting from Windows 7 client to Windows server console session vis Remote Desktop (Terminal Services):

• To connect to Windows Server 2003
  mstsc -v:<server_name> /F /console
  This allows to connect to session 0 which is physical console session.
  
• To connect to Windows Server 2008
  mstsc -v:<server_name> /F /admin
  Windows Server 2008 changes to architecture means that session 0 is only used to run services. To connect to a session which normally has keyboard and mouse connected use /admin switch.