I have several different areas of hedge as we have quite a large garden.
Earliest was planted 5 years ago to this mix
http://www.3fatpigs.co.uk/index.php?main_page=product_info&cPath=9&products_id=10
It is now about 5 foot high and 4 foot wide, I double planted it as needed a thick hedge in that area.. It is attractive through the year and yes there are jaggy bits but no problems with the kids.
I have planted some blackberry in it now too so that we get berries to use in Autumn.
Also have another small younger hedge of crab apple, the blossom is very nice in springtime and lots small fruits in winter.
Other ideas to add to a mixed hedge are hazel or damson (again edible)
My father in law has a hedge which is over 50 years old which was originally made by cutting down a row of trees which were on the border of the orchard and filling in the gaps with a mix. The damson and apple trees still bear fruit in the hedge.
Whatever you choose prepare the ground well, dig it over and add in plenty of well rotted compost or horse manure if you have access to it, ask around plenty stables glad to get rid but it needs to be well rotted.
Can recommend the 3 fat pigs nursery, I have ordered form them quite a few times now, the plants have been good and delivery speedy.