I can answer a few for you. I was not allowed to post some helpful links, so if there is a way for me to get them to you it'd be great, would help your understanding.
2) Buddhism was started by a prince named Siddhartha Guatama (circa 566 - 480 BCE), born in an area of present day Nepal. He gave up a life of pleasure and riches and the chance of a vast kingdom to become an ascetic, searching for enlightenment. The story goes that he first saw an old man, then a sick man, then a dead man, and then finally an ascetic living the religious life. During his time, the Indian area was in religious turmoil. The people were disenchanted by the Vedic religion and young men leaving to find enlightenment was very common. The Buddha went to many teachers, mastering them and then realizing they didn't hold the key to enlightenment. He went on his own and fasted to an extreme before realizing that was no way to enlightenment. He started eating again, and eventually he saw through the fog and became enlightened. (the four noble truths and the eightfold path). After his enlightenment it is said that Brahma (the highest god) came down and begged the Buddha to spread his Dhamma (teachings), which the Buddha complied with after some discussion. This is how Buddhism began. The Buddha traveled the country and preached the Dhamma to those that asked to hear it. He gained many, many lay followers and many, many nuns and monks.
3) The Pali Canon is the interpretation of the Buddha's teachings used by Theravadan Buddhists. Some say it is the most accurate and oldest, Each tradition will have people saying "this is the best text, the most accurate, the oldest" etc. etc. but it has found to be false claims. Scientists studying the history of the teachings have so far come to the conclusion that there is no extent "original" of the Buddha's teachings, considering that it was all orally passed down for hundreds of years. The belief now is that the Pali canon, Dhammapada, and many other interpretations came about near the same time and are obviously related by the basic Dhamma.
4) The Middle Way is the Dhamma taught by the Buddha. Dhamma is translated as; the truth, the teachings. What is meant by Middle Way is that it is not extreme. There are no extreme limitations set on a person, no extreme beliefs, it is in between both sides of the spectrum.
5) The three refuges are the: Buddha, Dhamma, and Sangha. The Buddha is translated as the fully enlightened teacher, the Dhamma is the teachings, and the Sangha is the community.
6) The Four Noble Truths are:
1- There is Unsatisfactoriness (it is very common to see Dukkha ((which is a Pali word)) translated as "suffering" but that is much less accurate than "unsatisfying")
2- The origin of unsatisfactoriness is attachment to desire (attachment to the three kinds of desire; desire for sense pleasure, desire to become, and desire to get rid of)
3- Cessation of unsatisfactoriness (the three aspects of this truth are; there is the cessation of Dukkha, the cessation of Dukkha should be realized, the cessation of Dukkha has been realized)
4- The way leading to cessation of unsatifactoriness (this is of course the Eightfold Path - Right View, Right Intention, Right Speech, Right Action, Right Livelihood, Right Effort, Right Mindfulness, and Right Effort. "Right" is not the best way to think of the Path. It makes it seems like there is clear-cut black-and-white wrong/right ways. It is more of how developed it is, fully or less than fully, etc. "Samma" is the Pali word used for it.
15) The major differences between Mahayanna and Theravada is the interpretations used (Mahayana use the Dhammapada, and Theravadans use the Pali Canon) and how much emphasis is put on ritual. Mahayana Buddhists are heavily involved with rituals and liturgies.
You should note that Mahayana has many sub-traditions under it (like Zen, Tibetan, Pure-Land, etc.)
This is all I can personally answer, much Metta to you