Are you getting an earful from parents or grandparents about which iPad they should buy? Read on for our guide to buying the right iPad for Mom, Dad, Grandma or Grandpa. Two bits of anecdotal evidence that there's a digital revolution in progress: In the past year, both my mother and my mother-in-law have purchased iPads. My mother uses a Windows PC at work, and has had a Windows-based laptop for the past few years. It was starting to get old and slow, however, and the battery doesn't hold a charge anymore. She was thinking about getting a new laptop or an e-reader, and asked me for guidance. My mother-in-law has had a Windows PC in her house, but never really felt comfortable using it. She had a Nook which sh