dilletante,

Thank you again for writing such a thorough and easy-for-a-simpleton-like-me reply!!! I have no edumacation in this stuff, so it's often difficult for me, as I am missing knowledge of the basics.

I think you would make a good teacher, if you were ever so inclined...

But for now one is probably as good as another if you are creating packages for hobby use, etc.
I am attempting a commercial venture. What is the biggest shortcoming of Inno in this regard?

It has been a little bit of a struggle adapting to Vista (still on-going?), but I have managed, mostly by myself (the .sys question has been the most perplexing issue to date, and as you see I guessed how to fix that myself), so it doesn't seem insurmountable? What am I missing?
Windows Installer packages allow a lot of administrative actions that do not occur in a home or other Workgroup setting. This offers many advantages over legacy installer technologies, the question is whether you need or want these advantages.
As an ignoramous, I can't imagine what they might be... Inno gives me a pretty good bit of control... Can you give me an idea of one or two of the biggest advantages over Inno in terms of administrative actions I might need? Or where I might find a detailed account?

I hope these questions and answers might help others, too. THANK YOU.