I just logged into PCLinuxOS on the same desktop just to test.
So the VirtualBox log from this shows :
00:00:02.008994 Oracle VM VirtualBox Extension Pack (Version: 4.2.6 r82870; VRDE Module: VBoxVRDP)
00:00:02.098794 Using XKB for keycode to scan code conversion
00:00:02.132326 VRDP: Statistics created: [full], enabled: 0.
00:00:02.143943 VRDP: VRDP: VD: Frames=10 MinMS=15 MaxMS=300 HistoryMS=2000 VideoMS=300
00:00:02.158300 VRDP: TCP server listening on port 3389.
00:00:02.161781 VRDP: Audio: rate correction mode 0x3.
00:00:02.161908 VRDE: loaded version 4 of the server.
00:00:02.161919 VRDE: [IMAGE]
00:00:02.161929 VRDE: [MOUSEPTR]
00:00:02.161937 VRDE: [SCARD]
00:00:02.161944 VRDE: [TSMFRAW]
That means it is ready for connection right?
Then I fired the laptop up and started rdesktop with IP address 192.168.1.2 and port 3389 and I did get an all black window. (If I had waited a bit longer I might have probably got the full desktop)
Then I started KRDC and using same numbers but additionally inputting the user name and password of the desktop user, I could see the desktop virtual instance on my laptop. Hmmmm....
But.... and it is a big one,,,, the performance is so teeth gnashing that I have completely given up on using this form EVER
I shall call this thread SOLVED. Thanks everyone.