Thanks to Haukur and Marco for the replies. (I got an e-mail from 'fjornir' with Haukur's name at the bottom. Are you one and the same or is my computer having a nervous breakdown?)
 
Bang goes my beautiful theory, but I would sooner be wrong and certain than hopeful and uncertain. However, though you have given me etymologies for 'kona', I am no wiser about the origins of 'ungr' and 'ing'. If their underlying meaning has nothing to do with 'young' or 'child of', are there any alternatives?'
Cheers
Jed