Rashi #1: You, Nebuchadnetzar, take your choice soldiers around it ¹ . So Yonason translates.

Rashi #2: The choice of Yisrael will gather inside it.

Radak: Laku'ach is Makor (infinitive) in place of a command, like "Zachor Es Yom ha'Shabbos" (Shemos 20:8), "Haloch v'Karasa v'Aznei Yerushalayim" (Yirmeyah 2:2]. The meat that will be dissected will be from choice flock. This is a Mashal for the officers and Gedolim.

Malbim: The meat will be from choice flock; it will be fatty, which does not burn like lean meat.

Rashi: He arranged the bones under the other limbs. I.e. the Giborim will fight for the sake of the weak, and they will rely on them. Dur is an expression of arranging, like "Tzanof Yitznafecha Tzenefah ka'Dur" (Yeshayah 22:18) - rows of surrounding troops. The Targum of Shurah is Dara.

Rashi citing Menachem: This is like "Ani Agdil ha'Medurah" (9).

Radak: Dur is a command, with the same grammatical form as Kum; it is an expression of Madurah (bonfire). Burn the bones under it! I.e. in place of wood, put bones under the pot, and ignite them. This is a Mashal, as if the bones of the innocent murder victims in [the city] will make the fire burn, and bring the punishments.

Malbim: He answers that [taking fatty meat] will not help. Even though they put from choice bones in the pot, they lit many bones underneath and boiled the pot more than is proper, until they cooked the bones inside. The bones underneath cooked the bones inside. This is a sign that the fire will be too big, for bones are not [normally] cooked. When hard bones are cooked, the meat is already ruined via overcooking.

Rashi: After all will be inside, the Kelim of the siege and war will come close to the city.

Radak: The fire will burn so much and boil the pot, to the point that even the bones, which are hard to cook, will cook. This is a Mashal for Giborim, who are strong like bones; they will perish and fall to the sword inside.