Does Dickens present Bounderby and Mrs. Sparsit critically or with ridicule in the first book of Hard Times?
Aside from the description of Bounderby as an old-looking bald man who probably "talked his hair off", we also have the ridiculous way in which he described his infancy, trying to be the epitome of the "log cabin" paradigm, and to the point of excessive effrontery trying to portray a sad and lonely childhood that supposedly made him the self-proclaimed warrior that he is today.
As part of the satire, the instances in which Bounderby tells stories about his past are plain silly: How his mother left him with a drunk grandmother that would sell his shoes for drink, how she kept him in an egg box, how he was born in a wet ditch and other ridiculous tales.
With Sparsit, chapter VII, Dickens brings out the satire in that she used to be a well-to-do woman who fell into Hard Times, but he focuses on how she is a "Powler" , which is a form of pedigree but he mockingly describes as
The better class of minds, however, did not need to be informed that the Powlers were an ancient stock, who could trace themselves so exceedingly far back that it was not surprising if they sometimes lost themselves - which they had rather frequently done, as respected horse-flesh, blind-hookey, Hebrew monetary transactions, and the Insolvent Debtors' Court.
So basically Dickens mocks the rich man's poor past with Bounderby's excessive self humbling which makes him look pretty ignorant and silly, and mocks the poor woman's rich past by mocking how Bounderby brags about him being her master and paying her "100 a year" for keeping the household of "Josiah Bounderby of Coketown" which is the name he gave himself.