I feel that its sad that Tolkien had no room for good Dragons in middle earth

[Annalaliath]

Did you know that spiders live on an all liquid diet. They have to inject their poison into the prey to predigest it.

Okay after that gross out, I would say that(no matter how much I love spiders)the spiders and the dragons both were all evil. The way that Melkor and all had corrupted them lead them to the point where they did not want to be redeemed. Shelob and her children(who she tended to eat) were all evil, she did not want to be good, after all she vomited darkness. Her children, many monsters and spiders, would not want to be good because they were evil. And after all this is not Disney(or Big Idea). I could go on about this for days repeating myself in different ways, but this has all been said before, hasn't it?