Gillian Reynolds

David Nobbs writes wonderful comedy because his characters invite odd situations to evolve around them. Here we have Tony (James Nickerson) and Sal (Olwen May), middle-aged, comfortably off, no kids. One morning their doorbell rings. It's Monty and Janey from America, who'd once put them up and to whom they'd said, on parting, "If ever you're passing..." No sooner have they settled them in the best bedroom than the doorbell rings again. And again. Wine is drunk, conflicts arise, accommodations are reached. Funny and curiously credible.

If the real world becomes too much, try Listen Against (Radio 4, Tuesdays at 6.30pm). It is so funny it will rearrange everything. Last week the pipe carrying BBC Three exploded, polluting all programmes around it; the BBC expanded into pizza delivery ("We can't leave it to the private sector..."); Gaby Roslin and Ed Stourton channelled to the centre of the Earth for Children in Need; the Dimblebys become News Brothers, a musical. Alice Arnold, Jon Holmes and company on Listen Against will brighten even the darkest evening.

Final show in the series. Stephen Merchant (last week's interviewee) talks to Jarvis Cocker about the disadvantages of wearing spectacles, being tall and gangly, rock festivals, rock idols and what really happened when the Pulp singer threw the contents of an ice bucket over Michael Jackson at the Brit Awards in 1996. It's on FM only because the special ecumenical Westminster Abbey Service of Evening Prayer, to be attended by both the Pope and the Archbishop of Canterbury, is on Radio 4LW from 6.00-7.15pm. Edward Stourton (as so often this week) presents.

This is a clumsy and tedious play. Its writer, Roy Smiles, has made cardboard characters even though they are drawn from life and, with the exception of the central figure, Graham Chapman, still living. To understand it at all you have to be someone who can recite whole sketches from Monty Python's Flying Circus (the dead parrot, the funny walks, e.g.). My mind boggled when I listened to the preview disc but I draw it to your attention as a piece which (a) shows how hard it is to write well for radio and (b) demonstrates the abiding power of great television.

Harry Shearer, voice of evil Mr Burns and hapless Ned Flanders on The Simpsons, American comedian, writer, and radio host, chooses as his interviewee Stephen Merchant, co-writer of TV's The Office and Extras, more recently an actor, standup and 6 Music presenter. The resulting conversation is most entertaining, a rare glimpse of comedy back rooms, a snowball of reflection on what makes something funny, how jokes grow. Merchant on his youthful experiments with a radio station in a hedge is sublime, their thoughts on comedy as a control mechanism is a tonic.

Very funny (and rather rude) pretend radio show, real extracts from actual broadcasts mashed up into fantasy fictional contexts (Jeremy Paxman running amok and being chased by the police, for example). Jenni Murray, Richard Bacon and John Humphrys appear as themselves but others (David Mitchell, Evan Davies, Steve Wright) are edited into parodies of themselves. Excellent cast, tight production, sharp scripts and a glorious capacity to make telling fun of radio's daily excesses. The Robert Peston competition is a wow. Alice Arnold presents, perfectly.

Rebecca Front (so good in BBC Two's sharp comedy Grandma's House) reads the first of Susan Maguire's trilogy of gentle, humorous stories about a romance. Here's how it started but then, eventually, came to a separation and division of goods. There's Andria who fell in love with handsome, passionate pianist Boris (they bonded over soughdough bread and butter) and Mimi, an elegant Italian greyhound who lay at his feet as he played. Tomorrow, what happens to Boris (and Mimi) after he takes up with Chiara, another artist. Wednesday, Chiara's tale. Yummy stuff.

Elaine (Katy Wix) hated school, so didn't learn much reading and writing. She's become her father's carer, unhappy but scared she won't get another job.

Ron (George Costigan) hated school too, with similar consequences. And he's a widower, getting on, getting fat. They both sign up for night school to make up for lost time. They meet. They get on well. But long habits make them scared of revealing too much about the reasons they want to learn now.

So what does playwright Gill Adams have in store for them to make it all work out? Look again at that title.

Paul Mendelson's canny, gentle comedy, about a woman up against religious tradition, was first heard on Radio 4 in the Nineties. It wears well. It could, almost, be about a woman vicar in a traditional parish or a nun who knows (as one or two sisters I have met know) that one of these days there won't be enough men to be priests. Tracy-Ann Oberman plays the new rabbi ministering to a Reform Jewish congregation who gets to know and like (and the liking is mutual) the orthodox rabbi and his wife in the neighbouring synagogue. First episode of four.

Once more the BBC salutes itself. Honestly, if they had to pay for the airtime to promote themselves, as they do constantly, the bill would be enormous. Here's ubiquitous Ian McMillan with a tribute to the longest-running sitcom in TV history as it reaches its final episode. Who'd have thought a comedy about three old men in rural Yorkshire could last so long, win so many hearts (if not mine) and make its corner of the Dales a tourist destination? Perhaps not even writer Roy Clarke and producer/director Alan JW Bell although their casting of the three originals, especially that of wonderful Peter Sallis and the late Bill Owen, was a masterstroke.