The speaker, as a third-person omniscient narrator, has an objective viewpoint. This means that the narrator does not display any bias towards any of the characters, nor any personal sentiment about any event or action. The narrator only provides insight into characters' thinking or their frames of mind and is not judgmental. The speaker attempts to provide the reader with as much detail as possible so that the reader may arrive at his/her own conclusion and assess characters, events and actions using his or her own judgment and critical skills.
It is clear throughout Things Fall Apart, that the narrator does not take sides and, even though some of the passages are filled with emotion, they are described more from the perspectives of the characters themselves, than from the narrator's. Since the narrator in this novel is also not personally involved in the events and the unfolding of the story, as a first- or even a second-person narrator would be, it makes it easier and logical, that the narrator would be offering an objective perspective.
I assume that the second part of the question is a reference to the values held by the cultures/people being described in the novel. Igbo culture, similar to practically all cultures in the world, is based on principles of respect, honour and the retention and protection of whatever is good in society as well as the defence thereof. So it is therefore, that a system of rules had been put in place to ensure that these values are learnt firstly, and then subscribed to. Any form of disobedience to these rules (call them laws, if you will) is punishable in some or other way, depending on the severity of the transgression. Just as in any justice system, there are seniors who are consulted for their wisdom and insight in issues of dispute. They also dispense justice after consultation.
Some of the more important values revealed in the novel are:
Respect for tradition and celebrations: Okonkwo did not show respect during The Week of Peace and was punished for it.
A man's value is determined through hard work: Okonkwo had always resented his father's laziness and worked extremely hard to become one of the most respected men in his village - the complete opposite of his father.
Respect for another's property: A man is not allowed to claim property or use another's (movable or immovable) without providing proof of his entitlement or permission.
A life for a life: Since every person's life is valuable, the taking of another's life means that a life has to be sacrificed in atonement or to replace the value of the life lost, as it was with Ikemefuna when he was placed in Okonkwo's care and eventually executed, in lieu of payment for the murder of Udo's wife.
Achebe uses a third-person omniscient narrator in this novel. We are privy to each character's private thoughts and emotions, but not limited to one character's point of view. There is also very little dialogue, which gives the impression of oral story-telling. The importance of oral story-telling is evident throughout the book, as the Ibo people honor and uphold the tradition. Although there is no dominant point of view, the narration shifts between characters throughout. So, even though we begin with Okonkwo, we also see the world through the thoughts of Ikemefuna, Nwoye, even the District Commissioner in the last paragraph. This shifting viewpoint allows the reader to consider all sides of the conflicts, & reach his/her own conclusions about their outcomes.
Even though the third-person narrator maintains an objective point of view, the interjection of vivd imagery/figurative language and Ibo vocabulary suggests an underlying purpose. Achebe has stated publicly that one of his goals in writing this novel was to combat the stereotype of Africa as the "dark continent." Thus, he presents his novel in the form of a tradition oral story, highlighting the richness of Ibo culture, and the dangers of immutability.