Please Salmon Trout, could we in the the future refrain from arguing on the fourm. As you yourself said "they are indefinitely available to the whole world", so people who read this post in the future do not want to see a bunch of people arguing. They want a post with good information and not what's beginning to happen in this post.
And for your info a ISO does not mean it has anything to do with pirated software. I can rip an ISO from any Cd I want to (including 98, XP, Vista, Linux, Mac OS X...).
Because we don't help with piracy.
Our job as a member of this forum is to help anyone who needs help. If someone is using an illegal copy of XP and he has a software install problem we (i would at least but I do hope others would) help him/her fix it.
I am certainly against anyone using illegal software. And if anyone came here asking where to download MS DOS or something I would certainly not help. This is the kind of situation where you "don't help with piracy", not telling someone "I won't help you because your not using genuine Windows".