How is the story "A Very Old Man with Enormous Wings" an example of "magical realism" and an allegory?
As an allegory, Marquez's story certainly has both literal and symbolic levels. On the literal level, there is the narrative of a desperate family whose illness and poverty are resolved by the appearance of what they call an angel. After they have profited from the angel, he becomes a burden to the family: "the exasperated and unhinged Elisenda shouted that it was awful living in that hell full of angels." The angel finally recovers his feathers enough that he flies away.
On the symbolic level the people of the village represent different types of people and their ways of solving mysteries in their lives. For instance, the priest, who has been indoctrinated in Church procedure, tries a type of exorcism, speaking to the angel in Latin, and accusing the devil of such "carnival tricks" as this dark angel. Then, he tells the villagers that he must write to the "Supreme Pontiff," the Pope, in order to obtain the final verdict from the highest courts. But, he words are not heard. Instead, a carnival does come to fruition, as all sorts of "the curious" come from far away. While no word comes from Rome, the mundane try find their own answers as to what the angel is, as people will do. The owners capitalize on the crowds and charge admission. Thus, they represent the opportunism of people. Finally, when all the newness and curiosity of the creature abates, people leave and the owners weary of the angel, demonstrating another human trait of becoming used to anything--even bored. The capacity to dehumanize a creature because of one characteristic is what makes the characters in Marquez's story allegorical types. The lesson of this allegory is that the Old Man shows people their cruelty, their uncertainly--in short, their true natures.
Regarding the magical realism of Marquez, the juxtaposition of ordinary with inexplicable and metaphoric produces both realism and the magical, suggesting that both attitudes are valid, and neither is sufficient by itself. For instance, the angel is magical, working miracles--albeit not planned ones as he cures the boy instead of having him die--and being like no other being alive. However, he is human, too, as he is described as "a drenched great-grandfather" looked familiar to Elisenda and Pelayo, believing him a lonely castaway from some shipwreck at sea. In another example, Marquez mentions that it has rained for three days, but a few lines later he writes, "The world had been sad since Tuesday." This juxtaposition of such a metaphor presents an idea that cannot be logically compatible with human feelings. In another example of this juxtaposition, Marquez writes,
In the midst of that shipwreck disorder that made the earth tremble, Pelayo and elisenda were happy with fatigue, for in less than a week they had crammed their rooms with money and the line of pilgrims waiting their turn to enter still reached beyond the horizon.
Magical realism expands the categories of the real so as to encompass myth, magic, and other extraordinary phenomena in nature or experience. Marquez clearly employs this magical realism as he juxtaposes spiritual phrases and occurrences with the mundane, creating a blurry distinction between the natural and the supernatural in the character of the Old Man with enormous wings.
The short answer is, only in a limited fashion. By that I mean, you can make allegorical connections between some elements of this wonderful story and reality. You can argue that the state of the angel represents a fallen or collapsed divine order. You could argue that the inability of the villagers to communicate with the angle represents the failure of faith and clear communication between religion/the divine and daily life. Those would be valid. However, there is a wild card element to magical realism, a sense that the world is too big for logical or allegorical frames. That would be things like the crabs, or the odd miracles done by the angel.