[Foxy]

You can get 25m green poultry netting standard height about 4ft, I think something like 107cm? I have a Hobby P450 battery energiser which can cope with 100m or X2 50m poultry nets easily.
This is the energiser I would recommend so easy to set up and reliable. Has never let me down! I would also suggest net testers so you can easily see how effective the netting is.

http://www.flytesofancy.co.uk/acatalog/Hotline_Hobby_12v_Energiser.htm

I would also go for an energiser that is more powerful than you need, for example our grass is growing quickly so the energiser has to work harder to ensure a good effective current as tall grass can drain the power.

They also sell green 25m netting.

Hope this helps!  

[Porffor]

Thanks link didn't work but i'll have a nose through.
might be worth going down this line rather than paying for a taller / stronger pen - which would mean bigger stronger posts! lol

Kids would have to learn not to touch too, or i'd have to use it when we are not in the garden. Our youngest is 3.

How do you get 'round' a door to the pen? Can you have two strips of it, or would i be better locating the door at the end? we'd only have to elec up 3 sides as one is hedge/fence next door.