Whether you and your grandparents lived under the same roof or never met, you might enjoy learning more about them by conducting a family interview with your grandparent or with someone who knew them. If you can interview several people about your grandparent, you are likely to gain a more multi-faceted story, based on the varied memories that most deeply impact different people. Here are a few suggestions for learning more and conducting a family interview, including lists of questions to ask:
http://www.aplaceformom.com/blog/2013-9-8-20-grandparents-day/
http://genealogy.about.com/cs/oralhistory/a/interview.htm
http://www.familytreemagazine.com/article/Now-What-Interviewing-a-Grandparent