Have you not read 2 Nephi. He tells us very clearly that death is a very important part of our eternal progression.No, they did not want their children mortal, nor did they hope to die themselves. They were deceived by the devil. "The serpent BEGUILED me" "Beguile" means to deceive.
That without it, we would be damned.
Adam and Eve clearly wants us to progress and they were willing to risk death after achieving immortality for themselves, to become mortal temporarily so that we would have a mortal probation in which to prepare ourselves for that which they, Adam and Eve, have achieved.