Beech, Field Maple, Tamarisk, Mock Orange, any conifer, Photonia, Privet, Buxus - quite a lot to chose from and depends on what height etc you need.

You could also contact readyhedgeltd.com. They are very helpful with suggestions.

You could choose to have a tapestry hedge, if its a long run then this would be a good option, giving you interest through the year with different shades of foliage and splashes of colour, incorporate some that kildermorie has suggested along with Some of the pittosporums varigated and bronze foliage, chuck in some Lonicera nitida Baggessons gold, the effect is dramatic and you would be the envy of all your neighbours, but be aware that some of the plantlings will be more vigourous than others so will have to be clipped a little more than the rest and of course be patient as they grow but long term it will look great.

Another vote for a tapestry hedge. Lots more interest... why limit yourself to one type of hedging which of necessity will have dull periods.

With a tapestry hedge you can have colour and interest all year around

I'm for the alternative option - having young children and plants which berry growing in the garden is a perfect and golden opportunity to teach them about what you can pick and eat, and what you can't. I'm sure all the houses/places you and they will visit over the next few years won't always be free of berrying plants, and they will at least have learned caution from you at home before coming up against berries. If the hedge is prickly (pyracantha, or berberis, say) the children are very unlikely to pick from it anyway, it's too uncomfortable.
Plants to exclude from gardens with children are the contact reactive ones, such as Ruta graveolens and Euphorbias, neither of which produce berries.

I agree with Bamboo - my new neighbour recently destroyed the most beautiful prolific rambling rose, as she was afraid her grand children would prick themselves on it!! I cannot see for the life of me, why any child would enter/play with a rose, and if they did, they certainly wouldn't do it again! You can protect them too much ... From a philosophical point of view, teach them instead to appreciate the 'beauty in the beast' rather than just the 'beast'.