In my experience - mainly in Ireland - storytelling is almost exclusively an adult activity.
We have been lucky enough to meet and record a few of the remaining storytellers here - some of them having stories lasting well over an hour in length (imagine any child sitting and listening for that length of time). We were told that one storyteller here in Clare would start his story on Monday night and tell a part of it each night until the end of the week.
The rule among the ones we met seems to have been straight narrative, no funny voices or gestures none of the tweeness you get from many revival tellers. Talking animals, fairies, giants, ghosts, cloaks of invisibility - all are taken in an audiences' stride as long as they are told with conviction.
For sources, the Penguin Book of Irish Tales and Duncan Williamson's 'The Thorn in the Kings Foot' are worth looking out for, so is Scots Traditional Tales (Bruford and McDonald editors – published by Polygon).
Tocher, the magazine of The School of Scottish Studies (particularly the early ones) have an endless supply. The School of Scottish Studies have issued a double CD of Scots Traveller storytellers that is well worth having, and the Irish Traveller organisation, Pavee Point has done one of the Travelling family, the Cassidys entitled 'Whisht'.
The Stewarts of Blair were among the best storytellers around, but they never did an album just of tales.
We compiled one consisting of Irish, English, Scots and Welsh tales and yarns for the Vaughan Williams Memorial Library back in the eighties called "… and that's my story", but I don't think it's available any more – you might try the library.
Jim Carroll