Some of my friends and family ask me for advice about technology and I usually make it clear that I generally dislike MS and their products and think they do not provide good value for money.
Increasingly both of the main options (Windows or Mac) utilise restrictive technology (e.g. DRM) to stop your computer doing what you want and doing what it is told by the content companies (i.e. music and film).
I think that Linux (see: www.getgnulinux.org) is now ready for most "civilian" users these days - although if you have some specialist needs or devices you may well be tied to a MAC or Windows.
Here are a couple of links to mainstream (i.e. not the geeky ones) reviews:
Dim Vista - Forbes.com: "Windows Vista: more than five years in the making, more than 50 million lines of code. The result? A vista slightly more inspiring than the one over the town dump. The new slogan is: 'The 'Wow' Starts Now,' and Microsoft touts new features, many filched shamelessly from Apple's Macintosh. But as with every previous version, there's no wow here, not even in ironic quotes. Vista is at best mildly annoying and at worst makes you want to rush to Redmond, Wash. and rip somebody's liver out."Bottom line from me: Don't "upgrade" to Vista unless you really are sure you know why you want it.
NYT's David Pogue on Windows Vista : The New York Times' Tech Editor with an amusing video review (Youtube) comparing the "new features" in Windows Vista with Apple OSX.
Schneier on Security: DRM in Windows Vista: This is a bit more techy but worth reading about the restrictive technology in Vista.