The second story might be Brian Aldiss's 1976 short story "Appearance of Life" (it is sometimes anthologized as "Talking Heads").
The story is told by a Seeker, a descendant of humanity, who has come to the planet Norma where a huge, seemingly abandoned alien structure is used as a museum of human artifacts. There, the Seeker discovers two holographic cubes from two different space ships which belonged to a married couple seperated by an intergalactic war, and which were programmed only to respond to the other person's face. The Seeker sets the cubes next to each other and lets them play out their story - it soon become clear that while the woman is expressing her undying love for her husband, he is admitting to an affair. The Seeker has a revelation that humanity itself is an artwork created by aliens, and no more free-willed than the holograms.
