I switched. I'm a PC user at work and was a PC user at home since version 2.11 of DOS! Like all of you, I hear Mac fans describing how good Mac is, so I got tempted to find out by myself, rather than being told. That's a scientific approach I believe. So I bought a Mac in Oct 2005, and I was positively surprised by its simplicity and reliability. See my blog: http://iswitched.skynetblogs.be.
In this particular case, the wife changing to Mac would be a benefit, because it would make Robert's life (as IT support) easier. And I cannot imagine a reason for the wife not being happy, by a stylish machine that delivers. Unless she runs very specila apps, she should not have any problem to switch. Most people just read emails and surf the web, plus watch movies and listen to music on their computers. All things that the Mac does perfectly.
Let's make a bet: your wife as an iPod and uses iTunes to buy music online. So the Mac is her natural choice.
What difference makes a Mac? Really, it works so fine and let's you focus on your daily tasks rather than fixing problems, updating anti-virus, anti-spyware or applying patches.
I recently bought a Wifi USB adapter for my Windows PC. I bought a cheap one, and let me tell you: it cost me 2 hours to set it up, on my Plug n Play PC! This is a real abuse! First, the driver is not signed my MS for XP. As a user, should I care? This message does not interest me. I bought a device that the box says runs on Windows XP. The rest does not interest me. Than the driver install failed. I had to uninstall the driver, reboot the machine and finally reinstall. Then at next boot, the device is not recognised. After troubleshooting, it eventually works. Thanks God, I'm a PC expert, but I can't imaging how your wife would have done it, should you be travelling that week... And now, at boot, I get a blue screen of death, unless I unplug the adapter!
I can tell you, that none of this exist on Mac. That's the difference. The price difference I spent on the Mac vs. equivalent (!!) PC, about 500$ is rapidly returned in saving time and effort on troubleshooting. Now I can really do my home videos rather than IT support of my PC...