Comparing Android to Windows on Tablets

I am very pleased with my older Nexus Android 7 inch tablet. But am thinking of writing an article for our club magazine explaining the difference between tablets using Android and Windows. See http://herc-hastings.org.uk/

Can someone please explain do those using Windows also have such a large variety of free safe Apps as Google proves for Android? All the free apps I downloaded from Google appear perfectly safe. Can the same be said under Windows. Many of the shareware etc. I have download for PCs using Windows over the years contain all sorts of nasties especially attempts to force you to use another Browser or Search engine.

Thanks