It's 20 years on, and Windows still doesn't have...

[chris]

Intuition was superior!

is

Microsoft's improvements to their GUI over the last fifteen years are... changing the taskbar so there is no text by default, and making everything look a bit different (in such a way that I've had three different window designs on screen at the same time under Windows, and it wasn't obvious which one was active).  There have been no functional changes at all (I don't include "mouse gestures" as they are a different way of getting to the same functionality)

The annoying thing is that Linux doesn't have any of this stuff either, although the GUI is amazingly more consistent.

[chris]

Most users would be too confused by it. undo/redo functionality would be better.

I don't see how it is confusing - however Windows doesn't have undo functionality in prefs either.  AmigaOS has, by default, in all system Prefs apps, "Reset to defaults", "Last saved" and "Restore".
 
Most people I've worked with click "Apply" before clicking "OK", despite me saying the "Apply" step is unnecessary.  The implication of the design is that "Apply" applies the settings and "OK" doesn't.  That's confusing.  As is Microsoft's insistence on requesters that have "Yes" and "No" as an answer, resulting in long paragraphs of explanation as to what each does, when changing the button text would have been more logical for the user.

If you want different settings for different users then you should setup different users.

Agreed, for the scenario given, different user accounts is the correct solution.

[chris]

Ideally, by the time I have to support Windows 8 in the business environment I will be out of this profession.

I said that when XP came out... and guess what?