<human>: Can you give me the gist of the text in a nutshell?

My grandpa means the world to me. He was my best buddy when I was growing up - always shuttling me places and taking extra special care of me. Oh, AND he's a total bad-ass:

Grew up in Kansas during the Dustbowl/Depression era; fought in WWII and the Korean War; had both knees replaced simultaneously; had a massive heart attack in the middle of the night, took a shower and then drove himself to the hospital; was at my grandmother's bedside every day, all day while she was in the nursing home for 8 years (she passed 15 years ago and he has a girlfriend now); had a pretty serious angioplasty a few years back; has broken both ankles in the last few years; beat cancer, survived a ruptured appendix (removed two years ago); still drives to Florida annually and around town daily...I could go on.

He's had - and still has - an amazing life, but I know it's not documented and I definitely don't know everything about him. When I'm home for the holidays (I'm in NYC, home is Michigan) this year I'd like to sit down with him and talk to him about his life, and somehow make a record of it all. I've many things I want to know, but what sort of things do you think should I ask about, Reddit? Specific historical events, or about certain experiences or details that I might not think of?
<bot>: I want to chronicle my grandpa's amazing, bad-ass life but I need help deciding what exactly to ask.