I know - yet another proposal to use a different Linux Distro but I am very happy with lubuntu (http://lubuntu.net/) which has a very clean look and just works.

On a side note: what still puzzles me is - for 15 years I've tried to explain the desktop metaphor to non-technical people among friends and family and now that we 24"+ screens and it starts to make sense, we move back to the single application paradigm...

Having installed Ubuntu 9.04 on various machines in my family (my mom's not exactly a power user), I can't really follow your argumentation. Nor the agitation.

A) No. Installing Ubuntu is easy. A proper dual-boot setup takes some experience - especially if you use Firefox/Thunderbird profiles etc from both OSs.
B) There is a problem with USB WiFi adapters but everything else worked out of the box. If you want to use the latest and greatest HW, stick to Windows.
C) It is a matter of use cases: my experience is that Linux is good enough. And yes, if you must use program X which only runs under Windows, well, then stick to Windows.
D) Yes, mainstream games suck on Linux. Get a console - PC gaming is dying anyway.

So again, if you have special requirements (hardware, software), stick to Windows, otherwise I found that Linux (Ubuntu in this case) is good enough for the average desktop user (judging from the small sample that I support in my spare time).

Oh, and keep your karma. You may need it when Windows 7 is out ;-)

--duck