Ooh! I always like it when something comes up I can answer. I'm going to leave judgement value behind and mainly answer a long the lines of what changed after the Norman Conquest.

Now the historiography has been a real long one but around the 20th century, around the rise of inter-disciplinarianism between history and other fields, the debate shifted from the changes the Normans actaully made to questions like 'to what extent did they change things?' or 'did they actually change things?' So depending on which historian you ask there was a lot of change or very little - either continuation or enlargement of past practise.

So for an example: Did the reforms under the 'Norman' Church happen because of the Conquest or the Norman kings or were they simply the culmination of the Gregorian reforms hitting the periphery of Europe several decades after there instigation in Rome? Or in a counter-factual view of history: would they have happened anyway if the Norman Conquest had not taken place?

Language: After the Conquest there existed a mixture of Anglo-Saxon English and common French vernacular which peasants would have spoken. Above that the new Norman aristocracy and clergy would have spoken Norman-French. Three languages spoken at the same time made post-Conquest England unique in Europe at the time.

Societal interactions: The Anglo-Saxon aristocracy and Church hierarchy was near totally replaced by Normans or Europeans. This wouldn't have too much of an affect because of the little interaction between peasants and aristocracy or higher churchmen. But particularly for the Norman-aristocracy's cross-channel holdings meant absenteeism on estates would be more common with work more likely delegated to overseers.

For a short time after the Conquest depending on the local area/situation the Normans lived as either an army of occupation or were able to mingle with the local populace. Also the Norman penchant for hunting meant that there was more interaction between nobles, trackers and lower class hunter.

Economic and population growth: During the Conquest one tactic of William I's was basically very Pyrrhic. When London would not open the gates to him he circumnavigated around it destroying buildings and burning the countryside around it, later in the Harrying of the North he would do the same thing but to a much larger extent, which when described by later chroniclers very much sounds like an induced famine.

Later though under the Normans there was a growth in the population and towns in England. The Norman aristocracy took a keen interest in the founding or designation of settlements to borough status to induce further growth, particularly near baronial castles. Furthermore archaeological evidence points towards a sharp increase in the issuance of coin circulation and the growth of both internal and external trade.

Law and government The introduction of royal forests or reserves for the King and later the aristocracy for there own pleasure and hunting stock meant that heavy fines were introduced to deter previous hunting and supplementation of diet by peasants. In the Peterborough Chronicle of the Anglo-Saxon Chronicles it mentions the disquiet of the English because of the above decisions.

Also in the Peterborough Chronicle is a reference to the peasants/people being annoyed of a rise in taxes and there view that the taxes were being used for William I to fight and put down rebellions in and around Normandy.

Church: Previously during the Anglo-Saxon period there was little uniformity in church practise or ceremony. After the Normanisation of the Church much of the English was replaced with Latin and the liturgy became standardised. Also during the period much of the parishes, ecclesiastical boundaries and bishoprics were recentred around urban centres.

In addition to the above there was an increase in founding and setting up of monasteries which had a (later) practise of hiring local labour for menial work.

TLDR: Common language became a mixture between French and English, socially not much difference, population and economic growth, a few more laws and general taxation complaints and Church reforms.

Bibliography

Primary:

1. Peterborough Chronicle from the Anglo-Saxon Chronicle

Secondary:

1. Barlow, Frank. The English Church 1066-1154. London, 1979.

2. Barlow, Frank. The Feudal Kingdom of England: 1042-1216. 3rd. London, 1972.

3. Bartlett, Robert. England under the Norman and Angevin Kings: 1025-1225. Oxford, 2000.

4. Barlow, Frank. The Feudal Kingdom of England: 1042-1216. 3rd. London, 1972.

5. Chibnall, Marjorie. The Debate on the Norman Conquest. Manchester, 1999.

6. Van Houts, Elisabeth and Christopher, Harper-Bill. A Companion to the Anglo-Norman World. Suffolk, 2003.

Edit: rewrote second paragraph to be more clearer. Edit 2: Realised the second Frank Barlow reference was after Robert Bartlett in the bibliography - just fixed that.