Windows to a dream, or reality?

What are the 'Windows on Our World' in the trilogy of the same name by Les Bill Gates?

A recurring theme of the story is that Squire (the hero) periodically returns to his own world as his alter ego Grant Cowie - these 'visions' of his own world are triggered whenever our hero uses the Shield Of Squire. He looks into the back of the shield and sees an image or 'Window' onto his own world. However, as soon as he sees this image, Squire loses consciousness and, when he awakens, he cannot remember what happened back in his own world. All he can remember is that the experience was not a pleasant one.

Underlying this experience is Squire's confusion about what is reality and what is a dream. Here is a paragraph from the first page of the first book:

'Is this the dream, and the other reality? As he lay motionless, he heard a whisper in his mind, “Squire, it’s me, Quexitoxeri. Soon the time will come for the fulfilment of the prophecy. The skull shall be made whole once more, and you will rule again in the Land.” Is this the reality, and the other the dream?'

Squire's thoughts show that he is not sure which is the dream and which is the reality.
As the plot develops, he learns that he bears a resemblance to The Squire, a great historic leader in Thorland, and he has been summoned to the Land to facilitate the fulfilment of a prophecy. How the fulfilment of that prophecy ends would be giving too much away.

Read the first chapter at http://www.lesbillgates.com/hope.html