I would be interested in what media consumption was like, as well as the telephone going widespread, what that was like and how it changed things.

Also folk tales from their childhood

It's an obvious answer, but anything surrounding World War II is fertile ground with that generation I'd guess. My grandfather is 94 and I finally asked him about his experiences, and it turned into an incredible conversation about race relations in the US, France, and Egypt, and how that impacted him when he returned to the (segregated) US.

Mom is 90. Just let that soak in a bit. She was 14 when Pearl Harbor was bombed. They heard about it over the radio Sunday afternoon. WWII changed everything. Living in a town that had a military base was life changing, also.

Mom kept a journal most of her life, including at this young age. She swears no one would be interested in a teenager's view of the war and she wanted to get rid of them. I told her once they were gone, there's no getting them back. After much cajoling, she gave me those journals a couple of years ago. Out of respect for her, I have not read them.

Are you trying to say people who lived through the entirely of the 40's? If so, saying "people born in the 30s" might be a touch more clear. My father was born IN the 40s (and thus lived through some of them) and isn't 70 yet.

To add to these, I would like to know about their music. Not just radio, but songs sung to them as kids, songs that they loved that didn't get popular and disappeared, how and where they went to enjoy music privately, what sounds aren't around anymore, and basically anything about music that's been otherwise lost to time. So much music has been written and not recorded for thousands of years, so any way to save something that important to culture should be preserved as well as it can be.

I'd be interested in any advice here. My mother was born in 1936 and has told me things such as seeing and tasting her first banana, watching the coronation with all her neighbours on the only TV in the street, riding on the Mumbles railway (the first passenger railway in the world), etc.

What more should I find out about?

As someone who worked on some projects using oral history I would say 'as much as possible'. I know that that is a really shallow answer, but let me explain.

You are never going to be able to predict what questions future generation will be looking to get answers on from your interviewees. I have worked with material that was recorded in the 80's and, whilst I was very grateful for the people who recorded it, I often found myself thinking 'why didn't he follow up more or ask more specific questions that are related to my subject'. Only about 1% of the recordings were relevant to my particular subject (f.i. the construction of a particular canal in my area) but some very short remarks and single sentences about the matter were very helpful in way the interviewer nor the interviewee could never have known.

I would say that interviewing and recording relatives or aquaintances who lived in that time period and submitting the recordings to you local archive is incredibly useful for historians. The more the better and as broad as possible. If you were to interview someone it is very useful to do some research aforehand. You want to know what generally happened in the area your subject lived in, just so you have a basic timeline you can adhere to to steer the conversation if needs be.

A very important bit on oral history is follow up questions. Most people will tend to repeat stories in a particular way, as they have told them many times before. These things are usually important to them and/or things they want you to hear, aka. the 'grand' stories. People who live through the 40's will surely mention the war and how they lived through it, but that's not always what a researcher is interested in. Oral history mainly serves as a tool to uncover the mundane, every day life of people and their way of thinking about various subjects: just look about how many 'I an an average x in -time period-, how would I percieve y' type of question that gets posed in this sub.

The art of interviewing is to subtly distort the standard narrative. Make people actively think back. I love to ask people about what the lay-out of their elderly home was, for instance. Usually they have to think about that, as they probably have never really incorporated that in any 'grand narrative' they have ever told. In thinking about that, though, they begin to visualize the past. Makes them think about how they felt living there. That way they may recollect things they have never thought about telling anyone as they felt 'normal' and mundane to them. Also it makes the conversation much more personal and they tend to open up a bit more. If you can tap into that for a bit you can uncover bits of history that may surprise you, as a relative, but can also be very useful for future historians.

Concluding: please go out and interview your relatives and submit the interviews to an archive. You might learn many things about your personal family history and preserve them for posterity. You may develop a greater personal bond with the person you are interviewing as a positive side effect. The recordings will most certainly be useful for future historians, in ways you might not know, much more so if you try to dismantle the standard narrative and ask for detail as much as possible.

I have four surviving grandparents, born in '34, '35, '40 and '41, respectively.

The first is Jewish, and had to flee to Sweden.
The next is very Danish, rural farmer-stock - they didn't have electricity until he was at least 10. (The third won't tell anything, he had an awful childhood. No point trying. The fourth is from Elsinore. She will probably answer any questions I have, as long as #3 isn't within earshot.)

What should I ask them?

What life was like for a black person before the civil rights movement

Just as a nice plug for a good cause, https://storycorps.org is a project that aims to have regular people record other people who have experienced history and might not be around much longer. They store the recordings as a way to preserve history.

I'm 79. I think that little attention has been placed on the effects of television on the way we think. I see big differences between people who grew up with tv and those who grew up without it.

My great grandfather who was born in 1922-23 and who lived through all the tumultuous events of Cyprus (WWII, the war for independence, inter-communal troubles, the Turkish invasion) died a couple of years ago... my biggest regret is that i didn't collect information from him, even if i was quite young when he died.. luckily, some of his stories have survived through his daughter, my grandmother, and i was told a very fascinating story about him the other day..

So my advice would be to collect anything and everything relating to their lives :) After all, when they pass away, there will nobody to tell their personal stories

What it was like to be a woman. My mind was blown talking to some older women. Stuff like how you couldn't eat at cafes or restaurants unaccompanied (in the US!) or be thought of as a loose woman. The exception was for the ones in department stores, I always thought it was weird Nordstrom's had a cafe. Stuff about sexuality and gender. So many of these unwritten social rules you just have to know.

My friend is currently doing her PhD conducting oral history interviews with women who were adults in WWII. She is collecting stories from their lives on the home front - working in factories or for police, activity in unions, interaction with American soldiers (this is in Australia). Australian government has the official stance that women's lives were bettered at home by the war but she is finding it's not the case at all. Very interesting stuff but it's increasingly crucial to collect these interviews now before it's too late.

My grandmother lived through WWII in Italy. Her father and uncle served for Mussolini while she apparently helped feed German soldiers retreating across the country. I'm just curious to know if there's a specific oral history projects/sites I should put her recollections into. I'm considering recording her life just because its so fascinating (i'm not really doing it justice in this short reply lol)

I'd ask about changes in big media and how it affected them personally. TV and rock and roll appeared and gained popularity while that generation were teenagers.