Aeschylus is often described as the father of tragedy. Like Sophocles, only seven of an estimated seventy to ninety plays have survived.
The Oresteia is the only complete trilogy of Greek plays by any playwright to have been recovered (except for a few missing lines). The trilogy consists of the plays "Agamemnon", "The Libation Bearers", and "The Eumenides", which together tell the bloody story of the family of Agamemnon, King of Argos, following his return home after the Trojan War.
The other suggested read is Prometheus Bound, whose authorship has come under debate since the 19th century. However, it is still typically attributed to Aeschylus by convention. Prometheus Bound is the first and only surviving work in a trilogy that also included the plays "Prometheus Unbound" and "Prometheus the Fire-Bearer". The tragedy is based on the myth of Prometheus, a Titan who defies the gods and gives fire to mankind, and for which he is subjected to perpetual punishment.
The other three surviving plays are "The Persians", "Seven Against Thebes", and "The Suppliants".
For the Oresteia, the 1 Penguin edition translated by Robert Fagles is a good bet. There is also a translation by 2 Peter Meineck from Hackett publishing. Christopher Collard has a translation which is published in the 3 Oxford World's Classics series. Either of these editions are well translated, and easy to read.
For Prometheus Bound, 4 Deborah Roberts has a translation published by Hackett that has been well received. Or you can just grab the 5 Penguin edition that also has the other three plays by Aeschylus ("The Persians", "Seven Against Thebes", and "The Suppliants").