I use open source as much as I can. Now and then I use XP to play games on, linux is still a while behind in bringing equivalents to the latest cutting edge commercial games to it.

At home I run a media PC, a desktop and a server... they currently run Ubuntu, Arch Linux and CentOS - Just to be confusing

I user CentOS for the server, as I administer RHEL servers at work so having a similar environment at home keeps me in the RHEL mindset. Arch is great for my desktop, which is a P4 and being able to build exactly what I want means that I don't need to upgrade my desktop and it still performs well enough that it doesn't annoy me. I use Ubuntu on my media PC, as I wanted something I could install and be up and watching movies in less than an hour - I love the rapid rate of development of the Linux kernel and Ubuntu desktop... especially in the areas of drivers, which wasn't always the case - in years past plugging random hardware into a Linux machine would have made me expect to spend an hour finding and compiling drivers, or support apps, and then manually editing config files to let the machine know it's there and then trouble shooting for an hour to find the one typo that means nothing works Recently I threw a DSE bluetooth dongle into my media pc, fired up my preferences and it had happily found my apple wireless keyboard and mouse.

Beyond the OS level I also regularly use: Chromium, Transmission, VLC, RhythmBox, Audacity, GIMP, Pidgin and many others.

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There's a wide range of IBM PC compatible hardware, and because MS Windows is the dominant OS on this hardware platform, all of it must work with MS Windows, and each manufacturer must individually ensure this. Any hardware that does not work with MS Windows will be returned en masse, and it will be 'a hardware problem'. Even if it's actually something in an update to MS Windows that's broken, the hardware manufacturer must deal with it or face oblivion.
Hardware manufacturers don't always ensure their hardware works with GNU/Linux, as this probably won't mean much to their bottom line. They may not even disclose information that could be used to write drivers. The task of writing drivers generally falls upon F/OSS people to do voluntarily, and they may have inadequate information available to do it. Consequently, some hardware might not have drivers, and some drivers may be a work in progress, especially for newly released or obscure hardware, or hardware that uses highly complex undisclosed interfaces. Issues here will always be 'a Linux problem', even if it's actually a bug in a driver the hardware manufacturer supplied, or a mismatch between hardware specifications and actual hardware function that went unnoticed because it happened not to cause issues with the MS Windows driver.
GNU/Linux is widely used on servers and supercomputers, and I think it is fair to say it is reliable if compatible hardware is selected (something that is never an issue with Macs). Of course this doesn't help you run it on your computer, but I think it's unfair to classify this as a case of F/OSS being unreliable. I don't think it's a problem with F/OSS at all, rather it's a case of minority players being disadvantaged, e.g. IBM OS/2 was in the same situation [EDIT: except on their own hardware, where they were better off.].