The richer character in oliver twist are, on the whole,happier than the poor characters.Is Dickens arguing that money leads to happiness? WHY or WHY NOT ? Relate your answer to personal and social value and themes ?

I think "happy" and "sad" are pretty relative terms. Dickens was conscious enough about this to make his characters reflect many parts of the human condition. Many, if not most, of the characters in the book are alienated from their society and each other. Oliver is an orphan, the quintessential outcast, and with the exception of Dick, the people with whom he associates throughout his childhood are deeply selfish and mistrustful, interested in their own welfare and no one else's. Among the thieves, there is no camaraderie; they often spy on each other and are ready to turn on each other at a moment's notice if it will gain them more money or freedom from jail. The "good" characters in the book present a rare little community of trust and goodwill, but they are so good that at times they seem unrealistic: no quarrel or misunderstanding ever mars their pleasant society. In addition, they are a small minority compared to the vast number of other characters in the book, most of whom are solitary and cut off from their origins and families, or associate in rough, shifting, untrustworthy, and temporary alliances.