What is the meaning of "Yivchar Lanu Es Nachalaseinu"?
Rashi: He will return us to our inheritance (Eretz Yisrael).
Radak: The inheritance that we had before, also now He chose it for us and returned us to it.
Malbim: The place from which will come out conduct of the kingdom and the creed - Tziyon. Even though now it is destroyed, Hashem will choose it for our inheritance. The beginning of dwelling of Shechinah was there; Yakov was shown the ladder. He saw also the Mikdash that will be built there in the future. This is why it says "Ge'on Yakov Asher Ahav."
What is "Ge'on Yakov"?
Radak: It is the glory of Yisrael and their beauty, that Hashem's honor dwelled in part of it, i.e. Beis ha'Mikdash. In this they glorify themselves over all nations.
Why does it say "Asher Ahav"?
Radak: This is the place that Hashem loved, i.e. Yerushalayim - "Ohev Hashem Sha'arei Tziyon mi'Kol Mishkenos Yakov" (87:2).