Here's my take. I've used Macs and PCs over the last 20+ years. FWIW, I love my Mac and my latest one has served perfectly well for a couple of years now. However, how you define "future-proof" is the key:
1) Do you mean you want to be able to upgrade components as they come out with bigger and better; i.e., graphic cards, etc.? Then PC is for you, unless you are willing to spend the money on a Mac Pro.
2) Do you mean you want the computer you buy to be usable for a long period of time (up to 5 years) without having to spend extra money? If so, it's kind of a toss-up with a slight edge to Mac. A well-maintained PC will last a long while, but you have to be diligent about maintenance. Macs require less maintenance, but this doesn't mean no maintenance. I still have running computers on both platforms that are 5+ years old at the office.
3) Do you mean you want to be able to buy one computer now and not have to buy one for a really long time (beyond 5 years)? Good luck with that one. Computers go obsolete pretty quickly and you are always going to want the latest and greatest.
My advice is not to buy based on such a vague concept as "future-proof." Buy based on what meets your needs now and for the foreseeable future. If all you do is web browsing, email and basic Office-type tasks, either platform will do fine, both now and in the future. If you have specific needs, then you need to judge the platform based on how well it meets those needs. For example, I would never recommend Macs to an Accountant since there isn't any great software for them. But musicians and graphic designers? I think the Mac meets their needs the best.
In the end, it's all pretty subjective. Most people here will suggest a Mac. I do too because it's elegant, easy-to-use and relatively free of problems. But that doesn't mean that it's right for you. Try Mac out and see if you like it.
