There's no need to forgive you, because you have done nothing wrong.
These forums are good, but for younger children I think they might be a bit complex... I dunno, it depends how quickly the children pick things up.
However, there is another forum system called
Beehive forums which has a really nice and simple interface, and will probably be exactly what you want.
If you need help, it is not like most places (where the developers are seemingly on another Plane of existance and cannot be contacted directly), as on Beehive the developers are easy to contact and are nice, friendly people who should be happy to help you with any problems you have. You can either goto
http://beehiveforum.sourceforge.net/forum for the test forum, though for a quicker response you might want to visit
Teh forum which is where the main community resides.
Beehive is released under the GPL which means that it is free for anyone to use.
So, that's the forum technology sorted... however unless you have website hosting which supports PHP and MySQL then it is not necessarily going to be much use.
Personally I use
Easily who are more expensive then some of their competitors, however they also have a very good service. Each time I've asked a query it has been answered quickly, and I very rarely get downtime... and when I do I can check the Easily site to see the reason for the problem, and it is usually fixed within fifteen minutes.
Other than that, I don't know what the current PHP hosting market is like, so it would be worth getting a second opinion... the people over at Teh forum should be able to help with this if you ask them nicely.
If you have any more queries feel free to ask and I'll try to answer as best I can.