Britannia, Gigantic Spaceship Lost in Deep Space

This is the starting point for my book. The occupants of Britannia are only aware of their immediate surroundings; in fact, they are not even aware they could be, or were, part of a much larger community.
Imagine a place where everything is provided: food, entertainment, everything. Imagine living in a community so structured around the level number on which you live, it even gives you your name.
Just one small problem - you are not allowed to read. Why are the council so frightened of such skills? Do they understand why reading is outlawed? Or are they just blindly perpetuating some ancient myth?
Imagine a small boy watching as his father is 'Introduced to the VAC'; executed, simply because he persistently revealed to the top council what he had discovered from reading in their hidden history, and knowing that your Mother has been banished to the lowest level simply for supporting her Husband.
Our little lad, for some reason, is taken under the control of the school responsible for educating the children from the top levels. Yet even under such close supervision, he has the courage to privately question the council’s logic. First, rather gingerly, he discovers a library, then two computers, ‘Fred’ and 'Spielberg'. Unexpectedly, and treated at first with just a modicum of suspicion, he is also influenced by his Aunt. Next, under council direction he is appointed one of the Council Readers, ostensibly to find some lost novels. What he discovers is a whole lost Universe.