Microsoft. OBVIOUSLY.
The only thing I will give apple is customer support and service. Microsoft is sketchy there. But I would to see how Microsoft's retail stores function to make a full assessment of how well they service things as well as customers. Online support is quite sucky.
OS wise, apple's ios is bland for my taste, and too restrictive by default. Even ios 7 is supposed to be just black, white and flat. They are pulling mac os engineers to put together ios 7. Last time they did that was at first launch of the iphone... mac os just looks gross, WAY too much skeuomorphic design, it's enough to give your grandparents as they will appreciate leather stitching.
Also, apple isn't so much a software company as they are hardware. They do make good hardware, software doesn't complement it well enough design wise. I believe Windows 8 would look SO much cleaner on a macbook than mac os. Microsoft Windows 8 wins this.
Surface tablets are supreme. Enough said. If I wanted a giant ipod touch, I would need shite eyesight and too much money to spend to send emails. Windows Phone is SO much better than ios, except app availability. That gap is being covered up quickly though, some big names have made it to Windows Phone 8, third party developers are taking it upon themselves to cover the rest. Metrotube is an amazing youtube app that google won't EVER match in any realm. Insdagram is that one piddle filter app of Instagram that for some reason people want. I found it to be a plus for Windows Phone. But ONE developer made a FULL FLEDGED client Instagram app, made over 50,000 dollars at least in a week with the app costing 1.49 and then later a free version. ONE DEVELOPER. Wow.
Product quality is murky, but I'll use the Surface tablets. They're pretty well built, they have their minor flaws, but overall rather excellent. OEM products with Windows, that's questionable.
Video games, umm...yeah, Microsoft Windows.
Driver availability, Microsoft Windows FOR SURE.
Technology wise, Microsoft. AMD, NVIDIA, Intel, and ARM complaint. mac os won't support a macbook from 2007. Windows 8 can run on an xp era PC usually quite fine. Sometimes graphics or NAE support won't be there, but a lot of the times it will be. More device capability and support over mac and ios. More innovation is done hardware wise that Windows can use that mac os won't ever, or apple won't ever support.
Look and visual style, I say Microsoft considering their hardware designs of their peripherals, Xbox One, Surface tablets, Kinect, and keyboards, ect. apple is pretty good at clean and simple design, but not innovative. Something like the Lenovo Yoga can't and won't ever happen in the apple camp. Windows 8 is the most drastic change of UI since GUI computing began. It's not based around iconography, it's about contenography. Where apple made strides in clean and simple hardware, they have failed on the software front. A tablet shouldn't look like it has depth or lighting effects with its software.
Virus and malware, Microsoft Windows 8. For the FIRST time however, Windows isn't on a list of security vulnerabilities anywhere. Kaspersky Labs claimed that I believe. They also have said that mac os x security wise is equivalent to Windows xp I think SP1 or pre SP1. Wow. It's true that mac os doesn't get the same viruses as Windows, because the ones that macs get can and will TOTALLY crippled the whole OS. That used to happen many years ago with Windows, usually these days malware on Windows causes glitches and issues, not something that has to be reinstalled. Usually.
Microsoft has outspent apple in terms of R&D. They have a whole Research branch of the company where some interesting stuff comes out. Things like the Midori OS concept is probably trickling down to Windows. Bing for example is being invested terribly with by Microsoft so they can have a native online search branch from Windows, Windows Phone, and to Xbox. They continually improve and tweak things for the form factor it's being used on.