In what ways have Hamlet's thoughts changed between his first and second soliloquys, and how have they stayed the same?

Hamlet's first soliloquy in Act I, scene 2, reveals his deep depression and his obsessive fixation on his mother's betrayal. He is mourning the loss of his father and even expresses a desire to join him when he says he wished the "... Everlasting had not fix'd / his canon 'gainst self slaughter"(I,ii).   Later, the reader learns that he is dismayed and disgusted that his mother married her dead husband's brother so quickly after the funeral.  As a good son, he thinks of his father as godlike, comparing him to "Hyperion" while reducing his uncle to a mere "satyr"(I,ii). He also chastises his mother for weeping like "Niobe" at the funeral but then turning to the physical comforts or "incestuous sheets" (I,ii) of another man.  Hamlet ends his soliloquy both angry and depressed and feels powerless to do anything but "hold my tongue" (I,ii).

Hamlet's second soliloquy follows an impromptu performance of Hecuba's speech from the Iliad.  Here Hamlet is still obviously emotional, but the emotions are aimed at different targets. In this instance, the player weeps and cries as he portrays the mourning wife. While watching the scene, Hamlet's anger is turned on himself.  He calls himself "a rogue and peasant slave" (II,ii) for sitting idly by while an actor can drum up more emotion for an imitation than Hamlet can for a real cause.  He curses and rants about his own cowardice and his uncle's villainy, but does not direct his anger toward his mother. However, Hamlet comes across as more powerful in this soliloquy.  Instead of keeping quiet, he devises a plan to perform a play that will "catch the conscience of the king" (II,ii).  He seems to be moving forward in his cause this time.