Actually, I've often managed to avoid using Windows.
However, having much experience supporting Windows and OS/2 and much experience in using Windows, OS/2 and Linux, I am speaking of what I know. Windows has many serious issues that affect product qualitity, including security. Some of this may be due to it's roots back in DOS, which means it evolved from a single user, non networked OS, which results in many compromises (All Windows versions from 1.x to Me were DOS based. NT, 2000 etc. were not.) with security tacked on as an afterthought. Also, many user functions require admin rights, which compromise security. When someone, with only user rights, encounters malware, the possible damage is greatly reduced. As a result, recent Windows versions have all those irritating pop up messages (Do you really want to do this, cross your heart and hope to die? <g>) to prevent malware from running, the same messages that pop up so often people tend to ignore them. On the other hand, I don't ever recall a Linux user app (not admin function) that required root privilege. With Linux, the home directories can be mounted non-executable, so that programs saved there will not run and directories containing executables can be mounted read only. These also make Linux much more malware resistant. Further, there has never been anything like that Windows "feature" of something in an email automatically running, which is a wide open door for malware. In order for such malware to run in Linux, the user has to take several deliberate steps, assuming he even has the rights to do them.
Now, how long can you leave your Windows computer running? My computer has currently been running for almost 6 weeks, but prior to that it was up for over 7 months. I previously had one Linux computer running continuously for over 2 years! Unlike Windows, the only software install that requires a reboot is a kernel update. There are no forced updates that may cause your computer to reboot in the middle of a presentation, as happened with Steve Balmer. When there's an update available, and icon on my task bar changes. I can then click on the icon, see what the change is and then allow it. I then continue on with what I was doing without worrying about the computer rebooting.