Stu, whilst it is true that our system of land tenure originates from the Norman feudal system you seem to be ignoring nearly a thousand years of legal development, including the Law of Property Act 1925.

A freehold tenure of land gives you absolute ownership of it. It is not owned by the Queen, or even the Crown (they are not the same). As a legal technicality, all title in land derives from the Crown ie the state. However this is only relevant when the true owner of a piece of land cannot be found (for example, if they have died intestate with no heirs), when ownership reverts to the Crown.

Anglo-Saxon society wasn't that much different from Norman feudalism. There was still a social hierarchy, and whilst more classes may have nominally owned land there was also a similar system of obligations attached to it. The Normans' system was perhaps more rigid, but nevertheless it eventually broke down through economic and social pressures.

The Norman invasion undoubtedly changed the course of English history. As with any invasion, the immediate aftermath was pretty horrific (although the preceding period was hardly peaceful). Whether in the long term that change was for better or worse is impossible to say.