Dead world. Probably not.
But a realistic case is something like 80% of Americans Die, roughly equaled by Soviet Losses. As Able Archer was a NATO training exercise, We can expect greater devastation in NATO/Warsaw Pact. You must figure that the world political situation is going to need days to use the bomb--the last of which are going to be laced with shrill screams for a people to evacuate. The more warning people have before the attack begins, the more people are likely to survive. If people have months the figure is going to be lower--cities might build municipal bomb shelters that could survive the attack, and there might be large enough food stockpiles to keep 1984 from being an unparalleled disaster. On the other hand, if one side actually all-outs the other with total surprise (like the Soviet Union's system goes offline for 24 hours and the USA takes advantage and nukes the hell out of it), that one side is going to get slaughtered. I don't know that this is really possible, although it MIGHT happen.
1984 is going to compound those losses with worldwide outbreaks of disease and famines. Humanity would probably survive such a war, but it will take humanity roughly 50 years to rebuilt all that it has lost. Mankind is tough, resourceful and undoubtedly a few people will survive the attacks. Indeed, between the resources of survivors from the extended nuclear area (of which there will be many) combined with nature's own resilience suggest that lessons will be learned.
By 1994, humanity would probably be back on its feet again. But it would be on a slipshod basis, with a hard life for the survivors and large patches of hopeless countryside. Eventually, nature takes care of things and washes radioactive fallout and other poisons into the oceans--not that this makes things better for some, but better for most.
The real question is how many nukes? Are the USA and the Soviet Union going to deploy ALL of their nuclear weapons, or just enough to disable their opponent?
Finally, I'd expect humanity to make a full recovery in roughly 2034--such a late date that much of the radioactive fallout will be gone and highly irradiated areas are safe to live in once again. With any hope, the crisis will bring humanity together for its own survival. It seems a trend of humanity to work together--even with former enemies--when the situation demands it. If humanity survives the crucible of nuclear war, the Cold War divisions will fall and large scale war at last becomes unpalatable.