Although he doesn't outright say it, Bob Ewell is so angry about his situation in the town that we can assume his hope is to rise above his poverty and disgrace. He must hope to be a more respected member of the community, making his three words: respect, honor, dignity. And also money - he certainly hates being stuck in poverty.
Atticus said the Ewells had been the disgrace of Maycomb for three generations. None of them had done an honest day's work in his recollection. He said that some Christmas, when he was getting rid of the tree, he would take me with him and show me where and how they lived. They were people, but they lived like animals.
The above quote demonstrates the need for Bob Ewell to better himself. It sets up why the man might hope so much for respect and dignity.
Mr. Ewell was sitting smugly in the witness chair, surveying his handiwork. With one phrase he had turned happy picknickers into a sulky, tense, murmuring crowd, being slowly hypnotized by gavel taps lessening in intensity until the only sound in the courtroom was a dim pink-pink-pink: the judge might have been rapping the bench with a pencil.
This demonstrates how much Bob Ewell is responding to being listened to. He is enjoying the attention, which in his mind translates to respect.
It was becoming evident that he thought Atticus an easy match. He seemed to grow ruddy again; his chest swelled, and once more he was a red little rooster. I thought he'd burst his shirt at Atticus's next question: "Mr. Ewell, can you read and write?" ..."I most positively can." "Will you write your name and show us?" "I most positively will. How do you think I sign my relief checks?" Mr. Ewell was endearing himself to his fellow citizens.
Similarly to the last quote, Mr. Ewell is swelling up because he believes that the attention of the crowd is showing him to be a better man than Atticus, a respected lawyer in town, and he is filling with pride as a result.