I haven't read any of Anders' actual philosophy, but this short interview was very easy to read, and it seems to give you a good idea of his thinking in broad strokes. Because it took place later in his life, he is able to discuss his ideas in their most developed form. He cites his two most important discoveries in philosophy as 1) the idea of the supraliminal, according to which certain things, such as the destruction of Hiroshima and Nagasaki, are too great to be understood by the human mind, and 2) the idea of the imagination as lagging behind reality.
The latter idea is striking, as we tend to think of our imagination as exceeding reality. But Anders argues that the reason humans do so many terrible things, for which they are "schuldlos Schuldigen" or innocently culpable, is that they do not know what they are doing, and the reason they do not know what they are doing is that they are incapable of imagining, or unwilling to imagine, what they are doing. Thus the moral imperative for Anders becomes to enlarge your imagination, that you may know what you do.
There's also lots of little interesting tidbits in here. I don't know why, but I found the way Anders spoke about his ex-wife Hannah Arendt funny: he kept saying "the woman who was my wife at the time." Anders also recounts an interesting night he spent with other students at Heidegger's house, when Heidegger made them compete to see who could hold a handstand the longest, and seemed put out to find that Anders, the lone jew among aryans, won. He also recounts a conversation before WWII in which Heidegger's wife spoke ardently to him about the need to exclude the Jews from German life, and Anders told her, Don't you see I am one of those you wish to exclude?