Re: I hate Macs!
It's funny you point out 'Inferior Hardware' Watso. This is where I have to disagree.
On paper, power against price, yes - Macs are more expensive. When you start to move into other categories like build quality, Macs start to become a good option. How many Ultrabooks are as well-built, reasonably-specced and have the battery life of a MacBook Air? Not many. In fact, as far as I'm aware all of them make some kind of horrible compromise to compete, usually battery life, screen quality or a 5400 HDD rather than SSD storage. The low-end Air is a compromise machine but to me the compromises are balanced reasonably against each other. Would I buy one? No. I'd want at least the 13.3 with the i7 and 8Gb of RAM and even then I want an optical drive, it's not a machine that meets my needs - but neither are any of the Ultrabooks and none of those are any cheaper.
That said, I'm really not sure about the Mac Pro.
I've had the same Macbook Pro since 2009. It's been a trusty companion and compared to cheaper PC laptops with similar specifications (except the eight-hour battery life), mine is the one that has survived the best. It's been dropped multiple times but it still works and the screen is still as good as the day I received it. All of the other computers I've had from OEM manufacturers in the past have developed major faults or were overly-noisy and generally unpleasant to use. My 2006 iMac still runs and has nothing wrong with it, all I've done is doubled the RAM. I've never had that with any desktop before even though my iMac is getting long in the tooth as a 32-bit only machine and can't run anything beyond OS X 10.6 (which is still probably the best version of OS X).
I'm not saying that Macs are for everyone. I'm a Linux dabbler too and really enjoy the customisability of the Linux systems that I've used and in the past used full-time and can absolutely see the appeal of a truly open operating system. I think that Linux is great and improving hardware support upstream can only be a good thing.
As for this disagreement over XP. Yes, you're right. You can lock down the Admin privileges and not allow users access to the root.
That's not the default setting though and how many people that buy computers that aren't advanced users like yourself will even know they can do that? Not many. If the default is to run as root user (yes, it's a *nix term but it's the best term I've got) permanently then when little Billy downloads that file from the Internet, it's going to compromise his machine and he doesn't have to give it permission to do so. At least in Vista, Microsoft made it harder to access root privileges by default.
So if Mum, Dad, whoever is running XP as a layperson, they are inherently more at risk than somebody running Vista, 7, 8, Mac OS X or any form of Linux.