Nuke issue resolved----> can think of Nuke-ing now!

*Ahem*  after working till 5.30 in the morning, I realise that I did indeed go Insane.

Well I reinstalled Nuke and tried again countless number of times, to export a QT straight outta nuke..

And as sheer luck (or probably resilience ;) ) I changed the compression option to  h.264  for QT

and   *whistling*  I got it right!!

So I assume my system did not have few codecs installed and I was asking Nuke to in those formats.