You blew your whole argument in the first idiotic line.
I'm sure you had a hard time concentrating when you wrote this since you must have jerked your knee pretty hard into the underside of your desk, but that's no excuse!
You say "Richard Stiennon at ZDNet argues that Apache is inherently less vulnerable to attacks than IIS, because it makes less system calls over the course of serving an HTML page, and is therefore less vulnerable to things like buffer overflow attacks."
He says: "Windows is inherently harder to secure than Linux."
Congratulations, you debunked an argument he wasn't making.