I read these a long time ago - but seeing as today is the anniversary of the liberation of Auschwitz I would recommend just about anything by Primo Levi.
While his writing is profound as individual works - if they're read in order it makes them even more moving and memorable. Start with If this a Man - then read what of the others you want but finish with The Drowned and the Saved.
Brilliant suggestion.
I cannot recommend the writings of Primo Levi highly enough, beautifully written, elegiac, bitter sweet, wise, horrifying, heart-breaking, understated, insightful and deeply, profoundly moving.
And I agree completely with jeremy h's suggestion about the order in which they should be read, in that Primo Levi's writings should be read in the order in which they were published, as this makes the experience of reading them svn more moving, more memorable and more profound: Start with 'If This Is A Man' , read the others (such as The Truce, Moments of Reprieve, The Periodic Table), but, above all, I beseech you, I entreat of you, read the extraordinarily powerful and deeply profound 'The Drowned And The Saved' last of all.