Gryffindor: James and Lily- stand up for what's right, even at the cost of sacrificing a normal, safe life together

Ravenclaw: Mr and Mrs Granger- while they know nothing about the wizarding world, they must have been open minded to believe the letter delivered to them by owl, and they seem to have been interested in Hermione's studies

Hufflepuff: Mr and Mrs Weasley- treat Harry fairly and are very friendly to him, are willing to take care of him despite not knowing him well at first

Slytherin: The Dursleys (apart from the child abuse)- they care very much about how people see them, Vernon wants his business to do well, and Petunia was envious of Lily's powers, originally wanting to have magic too