Well I can see it going 2 ways...
1) Total blood-bath for South Korean and US troops in Korea, since those north Koreans are mad and brainwashed to hate west from birth, I remember reading somewhere that Russian Spetsnaz visited N.Korean equivalent and they were stunned by how mental they were, most of them were brutally trained since teens and Russians struggled to out-perform them, even the hardened veterans from Chechnya and Afghanistan...
This could be a lie to boost N.Korea but I can see it happening... If you hand-pick children and create mindless killers they will be pretty good at it wont they?
Given the hard conditions that N.Koreans currently live in.. A war would not change their lifestyle dramatically... I mean if their troops are starving, at least they will hope for a chance to steal some NATO ration packs


Same cant be said about S.Korea... they are used to luxuries and food/water shortages will impact their morale greatly.
2) N.Korean troops and country surrenders quickly, in hope for food and better lifestyle.
But in the end I cant see a war coming out of this in all honesty... North Korea has no oil, China will not allow US puppet state so close to its borders and Seoul would be obblitirated within 30 minutes from N.Korean shell fire.. It would look worse than after nuclear strike. This war is in no-ones interest...