Amit,

First of all, I'm forced to write in English, due to forces beyond my control. My apologies.

I think that a Dictatorship with unreturnable debts and in an impossible fiscal situation is better than a Democracy in the same condition.
If a dictator falls, and a state of Anarchy is formed for a while, it will be much easier to use international pressure and support for the creation of a Democracy, then if a Democracy falls, due to it's governments inability to maintain a steady economy.
So I think it should be preferred to provide humanitarian aid to the masses until the dictatorship falls, then to provide the money which will help it endure, at the cost of the masses.

As for the effects of the New-Colonialism, it is true that this is quite a hypothetical problem, but let us not forget the way things actually take place: most of the times, the financial support for Dictatorships, given by international institutions such as the IMF, with the support of the international corporations and participating governments, is meant to maintain those regimes, due to the fact that they are easier to control and use in order to pursuit specific political and economical interests.
Neo-Colonialism is the occupation of a land and of a people, achieved either indirectly by a third party (A Dictator), or directly by economical control (A Democracy with un payable debts), and is a meant to help all of those with power, be it military or economical, to maintain and further their control, and to achieve their goals.

A loan which will be given to a country, coupled with proper restrictions and control on it's spending, will counter the Neo-Colonialistic cause, since it will not mean furthering the exterior control of those financial beings on said country, but will be a way of relieving some of the hardships which the people endure, and help create an infrastructure to a independent economy.
I also think that any loan given by international institutions, must be a part of a grander plan to promote Democracy and Peace, to protect Human-Rights, and to create a free and equal society. I think that some of the current institutions, especially the IMF and WB, will never agree to such a plan, since it directly contradict their intentions. In that case, I would chose the first option: massive humanitarian aid, if needed, and international pressure that will promote true democracy, and isolate the regime in place.