Always wanted to change my default port for remote desktop connection and happen to find a microsoft articles on this.

1. Start Registry Editor.
2. Locate and then click the following registry subkey:
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\
   Control\TerminalServer\WinStations\RDP-Tcp\PortNumber
3. On the Edit menu, click Modify, and then click Decimal.
4. Type the new port number, and then click OK.
5. Quit Registry Editor.
6. Restart the computer.

The orginal article is here

Regards

Hickural