Is it obligatory to give out money intended as expiations for past oaths, knowing that at the time, the questioner's life was characterized by major shirk (polytheism), or is it not obligatory to give it out and can be disposed of?

Since the questioner is afflicted with waswas (obsessive whispering), it is not clear whether her falling into major shirk (polytheism) is a reality or merely waswas. However, if what she mentioned is true, then she is excused due to ignorance, and she is not to be judged as an unbeliever. She must offer the necessary expiations, such as the expiation for an oath (kaffarat al-yameen), which is to feed ten poor persons from the average of what you feed your own families, or clothe them, or free a slave. But whoever cannot find [the means] - then a fast of three days.