If you are always holding their hands, they are going to be unknowing when they grow up.

Let them see for themselves why they shouldn't install the Java runtime and explain to them why it's bad.

My parents were very strict about me not using knives when I was growing up, and it took me 30 years to finally get mostly comfortable with using knives in the kitchen. Yes, I've never cut myself with a knife, but I also rarely cook as a result.

Sure, and that's a good idea. But I believe OP's point was the inclusion of the [crap|mal]ware in the first place, not what a reasonable response to it is.

That makes you a good parent. As would the converse.