Well, the Ring is Sauron, in that it is merely an inanimate object infused with part of his fea. It can have no 'will' or consciousness not derived from him.
Possession, and especially the active use of the One, is an act of opening one's mind and soul to being overwhelmed by his superior spirit. The Ring conquers by immersing the bearer in that spirit to the point that he becomes an extension of Sauron, sharing the latter's desire for power to enact whatever dreams the bearer holds. It is that desire for power beyond one's native abilities that sows the seeds of destruction.

It feels a bit incongruous after rereading this thread to go back to talking about "The Land of Shadow," so I'll ease into it by not completely agreeing with past-Formendacil. The Ring is not sentient, to my mind, but it does have a kind of soul, for lack of a better word--to go a bit Latin, it has an animus--i.e. something that animates it. Because the one thing we do know is that it acts. To say that it "knows" things is probably only true analogously, in the sense that a computer "knows" things or a magnet "knows" north. There's a recent article I've seen making the rounds on Facebook comparing how the Rings work to software (or, rather, malware), and I think the "able to work things out, but does it actually think?" dynamic of software is actually a decent way of approaching this question.

Going into this chapter, although the Ring is clearly omnispresent to Frodo, it isn't sonething as weighty to the reader, though it is making itself felt more than it has through most of the book (compare with the Ithilien chapters, for example). Instead, the emphasis, seen through Sam's eyes, is on the external dangers: pursuit, thirst, the terrain. Even his concern for Frodo is more directly seen as concern for Frodo's physical well-being than the impact of the Ring, which is not to say that Sam doesn't care about Frodo's psyche, so to speak, but he doesn't try to address it, beyond offering signs of hope where he sees them. He fixes what he can fix, which are the physical conditions.

The Morgai fascinates me as a not-quite-barren desert. Its terrain is pretty much completely missing from the movies (at least, I remember nothing). Although it's not a hospitable environment, I'll admit the tourist in me would like to visit, like visiting a desert or "the badlands."

We also get a little more of the internal organisation of Mordor here than we get anywhere else: the industrial sector in Udun, the breadbasket in Nurnen, the castle of Durthang, the roads and bridges. Mordor always feels more "real" to me in this chapter as a result, rather than just a barren desert out of which faceless hordes swarm like locusts.

One thing I find very interesting about Book VI is that, up until the Field of Cormallen, the viewpoint remains with Sam as it had since Shelob. It's as if Frodo by this point is no longer 'relatable' enough to serve as the reader-proxy.

(Always in LR the reader-proxy is one of the hobbits (or Gimli as the nearest-to-hobbits member of the Grey Company))