Whatever the reason for your dismissal, to answer the question, why did you leave your previous job, you need to calmly and confidently. Experienced HR Manager will pay attention not so much on the meaning of your words as to how you answer the question. Try not to worry and not to get confused, especially not to invent. Calmly tell the real reason, but if it does not apply to conflicts with staff and leadership.
Don't talk about the conflict, even if you are sure they are right. Do not blame your former boss or employer. Remember that your partner, especially if you are dealing directly with the employer, mentally loses the situation, how are you going to do if not work at this workplace. No one wants to be spoke of him badly. This is especially true of small towns, where many business leaders know each other.
In that case, if your partner already knows about the incident conflict, not to go into details, tell him that this case is unique in your working life and associated with special circumstances. Respond positively about acquired experience and skills.
There is nothing wrong, if the reasons for dismissal you call unfulfilled salary expectations and the inability to realize themselves in the workplace. It is a common phenomenon and quite natural reason, especially if your hands are dependents. Indicating the reason for the low earnings, you should be sure that the proposed job will allow you to earn more.
It is natural to neutral will be perceived, if you specify as the reason for the upcoming reorganization, the impossibility of the realization of its potential or career growth, the desire to try yourself in a new activity.
Your answer should be thoughtful and logical. You can say that on a previous job you have achieved certain goals and your personal contribution was highly appreciated, but the prospects for myself, you see. In this case, you will look very dignified and, most likely, ceteris paribus, the vacancy will be offered to you.