I was, basically, you a few years ago.
My first brush with Linux in the late '90s was pretty frustrating. I tried out Red Hat Linux (I think it was 5 or 7) on a computer that, surprisingly, I still have, though at the moment it's sitting around unused. I don't even remember whether it currently has a hard drive in it with an OS installed. At the time, Red Hat Linux absolutely could not, under any circumstances, make the onboard integrated graphics adapter on my cheapass low-end motherboard work worth a damn. It was awful. Since I was playing with it only for personal hobby interests, I ended up walking away.
Later, I came back to Linux. Things have changed. Oddly, that particular computer still doesn't like unix-based OSes at all. I've managed to get two non-Windows OSes installed on it effectively, and the other dozen I've tried simply wouldn't work properly. Of course, out of the four different versions of Windows I've installed on it, only two of those worked as well. If there were another eight versions of Windows that I could try on it, I wouldn't be surprised if none of them worked either.
In my second run at learning Linux, it was more for business reasons than personal reasons, so I had more incentive to stick with it. I also wasn't dealing with that same computer with new installs, and discovered that Linux installs just fine on basically everything else. Better yet, I don't have to keep track of driver disks for Linux like I do with Windows, so when it comes time to reinstall, I never have the problem of not having drivers. It's a wonderful thing, I tell ya, especially when I keep occasionally coming into possession of third-hand computers that make perfectly good servers and low-end desktops.
If you use your computer for getting real work done, I suspect you'll end up going the same route as me if you give Linux a fair spin. I simply found myself using Linux more and more, and Windows less and less. At this time, I don't even have a Windows system running here. Everything I have running has Linux on it. Even my consumer-grade router/firewall appliance has a pared down, limited, custom version of Linux on it (though that was a matter of pure chance rather than choice, and I intend to replace it with an OpenBSD router/firewall made out of an ancient laptop with a broken screen).
The more I used Linux, the more I discovered I didn't want to use Windows. Windows is cantankerous, unpredictable, incompatible with everything (including itself) from one version to the next, unstable, more maintenance-intensive (especially for security reasons), less configurable and customizable, slower, incapable of being as pretty as Linux can be, and encumbered with high costs and frightening licensing issues.
Once I got used to the concept of good software management ("good" is a distinct understatement in the case of Debian's apt), I found myself wondering how I managed to put up with the nightmare of Windows install wizards, installation CDs for every damned program I might want to use, having to hunt through hundreds of websites and thousands of Google hits for useful programs, and so on for as long as I did. The necessity of running redundant AV and antispyware software, software firewalls whose resource-suckage brings the term "event horizon" to mind, and the existence hundreds of megabytes of software I don't use that cannot be removed all conspire to make Windows a miserable user experience for me in comparison with Linux.
At this point, even though there's more money in it, I mostly just refuse to support Windows issues when I have the chance. I don't need that kind of stress.
I had a computer crash today. It's a remarkable event, whereas with Windows it's remarkable that I was able to keep computers from crashing. Unlike Windows, though, with random blue screens of death and lock-ups, this crash was due to accidentally unplugging the computer while it was running. Whoops, my bad. My main server, meanwhile, hasn't crashed since August, when I moved to this town and plugged it in. It's a file server, application server, music server, mail server, web development test server, backup server, and about six other things as well: I use the hell out of it. It actually became a server because the monitor I had plugged into it died just before I moved here. Unlike what would have been possible with Windows, I was able to use a VNC variant to attach to its running GUI session to save data from open applications, and I have since then been able to uninstall applications I no longer use on the thing since it is no longer pressed into service as a desktop system. It's not even running a GUI now. Try that with Windows. Really.
The only things I can think of that might make Windows a better choice for some uses by IT pros who are reasonably intelligent are these: computer games and Windows familiarity/support.
When one's livelihood depends on knowing Windows, it behooves one to stay current on Windows matters, thus prompting one to keep using Windows at home. When one responds to support calls related to Windows, it (almost) always helps to have a Windows system near at hand.
With Cedega, I hear wonderful things about normally Windows-only computer games running well under Linux. That being the case, I have a hard time imagining much reason for going with Windows even for gamers. Of course, there still may be gaps in the ability of Linux to support these games. I don't really know -- I'm not much of a computer gamers. I only have second- and third-hand accounts to inform my understanding of the situation.
In the end, I have two marketing slogans for you to point out some of the differences between Windows and Linux. The first slogan was created by Microsoft marketing flacks, and the second by me:
"Windows. Where do you want to go today?"
"Linux. What do you want to get done today?"
If that doesn't strike you as a reason for an IT pro to use Linux, I don't know what possibly could.