Hislop's going into battle for 'conchies' and trainspotters

' What you seem to do," Ian Hislop was recently told by one of his acquaintances, "is go round talking to old people about dead people." It is hardly the most flattering critique of a broadcasting career that now boasts a back catalogue of more than 20 serious television documentaries – made between appearances as team captain on Have I Got News For You and the day job of editing Private Eye – but Hislop seems quite comfortable with the appraisal.

Talking to older people is something, "I'm very happy about" he says. "I greatly enjoy that bit of it. I feel that if you make the interviewees feel comfortable they will be more entertaining and I like the idea that you can make people tell the story." Sitting in his office at the top of a rickety staircase at the Eye, he expresses the view that modern television executives are missing something as they relentlessly chase the eyeballs of the nation's youth.

Hislop has never yearned to be down with the kids. He was seen as a bit of a fogey even when he took up the editor's post at the satirical magazine 22 years ago. And he was only 26 then. "I think [television bosses] are slightly deluding themselves. Like everyone else, I believe that young people tend to go out and older people tend to stay in and watch the telly, so catering for them is a fairly safe bet," he observes.

Not that he is seeking to follow Richard Ingrams (former editor of Private Eye, now at The Oldie) and become a seniors' champion. Rather, he wishes to bring to life those stories that other film-makers might write off as being fusty. "I'm very keen to present interesting programmes about things which people might assume to be dull," he pronounces. "If I've got any mission, that is it."

But his next two programmes could hardly be regarded as boring in their subject matter, covering the contentious issues of the ruthless axing of vast sections of the British rail network (for BBC4) and the stories of those who risked a death sentence to object on principle to fighting in the trenches of the Great War (that one for Channel 4).

The first documentary, which goes out this Thursday, investigates the background to and impact of the notorious Beeching Report of 1963, which greatly reduced the scale of Britain's railways, casting civil servant Dr Richard Beeching as a hate figure for a generation of rail enthusiasts, most notably John Betjeman. Hislop does not spend his weekends at the end of platforms, furiously noting down locomotive numbers and forking down Pot Noodle, but he is a daily rail traveller from his home in Kent into London Charing Cross. As such, he has much experience of commuter misery, with his television profile leading his fellow passengers to think that he might take up cudgels on their behalf ("They pass on their complaints to me as though anybody would listen to anything I say").

At the conclusion of his programme-making journey, Hislop has some sympathy with both sides of the argument. Though Beeching was "a classic technocrat" who "came across as very arrogant" as he closed line after line, he was also unfairly maligned. "The monster Beeching of folklore is slightly exaggerated, even I had to admit that. Part of the deal is that the politicians needed someone to make those very unpopular decisions and he was absolutely the person."

But then again, Beeching "didn't take on board the social argument" of rail travel and Hislop "ended up thinking that the Betjeman protests had a point, they really did". The same tension between the value of public services and their cost to the taxpayer is replicated in contemporary arguments over the future of Post Offices, he notes. "The thing with these economic arguments is that they always change, nowadays they are opening up bits of line that Beeching closed because we don't want to fly everywhere anymore and fuel costs are different and the environment is different. What he said was efficient isn't necessarily."

Hislop's fascination with "Conchies" (conscientious objectors) stems from his exploration of his grandfather's war service record when he participated in the BBC2 series Who Do You Think You Are? This will be the sixth history documentary he has made for Channel 4 as part of the Not Forgotten strand. Though he has great respect for those who fought and died, Hislop asks whether we should do more to remember those who fought for the right not to bear arms. "I was interested in this particular group of quite bloody-minded but really pretty impressive conscientious objectors who just said 'No, the whole thing's madness, I will not be party to this' against a backdrop of unbelievable pressure from family, peers, and the Army."

In making The Men Who Wouldn't Fight he uncovered an extraordinary Great War football match to compare with the famous Christmas truce kickabout played in no-man's-land between opposing troops. On the beach at Boulogne in 1916 another game took place between British conscientious objectors who had been taken to France in the hope of convincing them to join the war effort.

"It was a very bizarre incident, they shipped all these conchies over to France thinking we'll get them over there and then they'll cave in. Of course they didn't. We filmed where they'd been on the beach and had a game of football and then a cup of tea. The army got them in a parade and said: 'We've had a court martial and you're all sentenced to death'," says Hislop, putting on an officious voice. "There was a big pause and then 'but we've commuted the death sentence to life imprisonment'. They were hoping to scare the pants off them but the Prime Minister made it absolutely clear that no one was going to be killed for conscientious objection."

Such has been the impact of Hislop's Not Forgotten series that a plastic box on the floor of his office contains four lever-arch files of correspondence from viewers. "Look at it! Hand-written, typed, emails. I mean it's fantastic – if you do something that connects with people they are incredibly appreciative." His respectful treatment of the legacy of Lord Baden-Powell ("a very unfashionable figure") in the BBC documentary Ian Hislop's Scouting for Boys drew a resounding "dyb dyb dyb" of approval and brought a flurry of invitations to scouting events.

He has another idea for a grand television project but has so far failed to convince those youth-obsessed commissioners. "It's about booze really. The essential split in Britain between the Puritans and the Merrie England brigade, from Hogarth to Wetherspoons on a Friday night. That's the programme I'd like to make. It's got a lot of history in it as well as a lot of drink, so I haven't sold that one yet but I keep trying. It's got riots, gin, you name it ... don't you think that would be really good?" Surely an opportunity for "Trebles all round" in the BBC bar, as the Eye would say.

'Ian Hislop Goes Off The Rails' is on BBC Four on Thursday at 9pm

'Not Forgotten: The Men Who Wouldn't Fight' will be shown on Channel 4 on 10 November