The Web Planet will definately give you the feeling this is a childrens show. That is not to say that's a bad thing or that it is a bad episode. I have not watched it in some years but it is very good. I find that the acting and staging is very geared towards a kid audience. It seems at times that the actors playing the alien race move in exaggerated ways and the way the aliens speak are somewhat simple. Web Planet tho is very bold in that it utilises very elaborite costumes and make-up to protray an insect race. I still recommend it. I think it's quite good.
The Visitation is also a pretty decent story. I don't think I've ever seen it start to finish tho.
"The days have gone down in the West behind the hills into shadow...How did it come to this?"