In my opinion, trying to keep them "protected" from the things that can be found on the internet, is only going to make them even more curious, and have them go else where to look, away from your logs, and nanny programs. Either that, or find the way around these things.
I think it best to just sit down and explain to your kid, what needs to be explained. For example, if you're trying to protect them from porn, it's time to have that birds and bees talk, but be open about it, and not come off as if it's taboo.
If you're just open with your kids, chances are very good that they'll actually listen to you, and turn out just fine. If you go around blocking things, or forbidding them from going to certain places, it's only going to make them want to know what's so terrible that you're trying to keep them from it.
I'm no child psychologist, but I was a kid once
I know how I, and all my friends, and the kids I knew from school acted.
Just talk to your kids. Not as in "I'm the parent, and my word is law", talk to them with respect, and that will have a lasting impact on them that demands, forbiding, and strict rules will never have.