A caricature is a description which simplifies some features of a subject, while exaggerating others. These descriptions can be complimentary or insulting, but they often have a symbolic meaning. Swift uses caricature in his descriptions of Liliputians. For example, Lilliputians are extremely small, and their conflicts and divisions are overly simple and petty (such as low heels vs. high heels, or the practice of boiling eggs). This caricatures are meant to provide a veiled criticism of English culture.
While many might say the fridge needs to be opened first to prepare breakfast, note that it does not say that the parents are in the house, and therefore they would need to be let in. Hence the answer of what to open first would be "the door".