What is the meaning of "Katzatz"?
Rashi: He cut off the doors, which were 1 of gold.
Radak, from Targum Yonasan: He peeled the gold off the doors (they were covered with gold).
The doors were of wood, and only covered with gold (Melachim I, 6:34)! Sancheriv demanded gold and silver. Why would Chizkiyah send the doors themselves? Brachos 10b says 'v'Shagram', which implies the doors themselves. (We cannot learn from "v'Yitnem" in our verse. It refers also to the Omenos.) Perhaps the doors were removed or ruined (refer to 18:16:3:1 and the note there), and Chizkiyah or another king made gold doors in place of them. However, gold is soft; it is not so proper for doors. Some texts of Rashi say 'Hayah' (was, singular). If so, perhaps Rashi refers to the plating, like Radak (refer to 18:16:1:2). (PF)
What are "ha'Omenos"?
Targum Yonasan: Sekofaya. Radak - this is like he translated 'Miftan' to be Skof (lintel).
Why did Chizkiyah need to cover the lintel with gold? Shlomo already covered the Bayis with gold!