Whoever still remembers her should keep them as a precious memento. After that, tell the younger generation to do as they will with them. (Although firstly I would ensure that the old photos are scanned and put on the family tree, or, if there is no personal FT, research through other family trees and offer them for entry should you come across this lady.) The books should be donated to a charity shop. The stamp collection may be of value, get it appraised. And the same for auntie's goods.
I have a couple of letters from my mum...my siblings are long gone. Himself will read them again if I go first (he and my mum loved one another to pieces) and then destroy them (there are no children). Ditto from my aunt/godmother. Photos have already been categorised and scanned into the site. Others have been distributed to appropriate people and, again, what is left will be destroyed. If I follow the family trend (females going on to their centenary or close), I could last to 100+; if I am still here on my 100th, and still compos mentis, I shall destroy them myself but thoroughly enjoy the memories they will bring at that particular moment. Am I being too sentimental? Maybe so, but I have had - until now - a wonderful life and I treasure being able to remember the times gone by by looking at/touching/reading these treasures.