What is the meaning of "Hechadalti"?
Radak #1: It is Hiph'il (I caused to cease).
Radak #2: It is like Hachadalti with a Kamatz under the Hei, Pa'al (to cease or abandon); Targum Yonasan is like this.
What is "Dishni"?
Rashi: It is my oil.
Malbim: It is a metaphor for attaining Chachmah and an influence of prophecy. Ru'ach ha'Kodesh is called Kavod in Kisvei ha'Kodesh.
Why did the Zayis decline to be king?
Bereishis Rabsi (20:15) The Zayis represents Osni'el. He did not want to abandon his Torah, which illuminates the world like olive oil.
Malbim: A fortunate man does not desire authority, for it ceases him from his spiritual perfection, to be a slave to the nation to oversee their affairs. 'Do I give to you authority? I give to you slavery!' (Horiyos 10a-b)
What is "Lanu'a Al ha'Etzim"?
Radak citing Targum Yonasan: It is to be king over them.
Malbim: It is to oversee their affairs.
QUESTIONS ON RASHI
Rashi writes that Dishni is oil. How does oil honor people and Hashem?
Radak #1: It is used for lighting [the Menorah] in front of Hashem, and for people.
Radak #2: We offer Menachos with oil to Hashem, and also people consume it.
Targum Yonasan: From it we honor in front of Hashem, and it indulges people.