Well, you create file1 with "microsoft" in it and file2 with "linux" in it. When you run diff on the two files you'll find that they have nothing in common.
This answer is certified not to help the OP in any way
Comparing an OS to a corporation is pretty futile. One difference between "linux" (not a linux distribution, but "linux") is that Linux is a unix-style OS kernel and Windows is an OS with lots of other bits, included as a monolithic whole.
A Linux distribution is something different, and there are several major layers to this. One is the Linux part (the kernel), one is a whole pile of utilities and libraries and another layer is GUI's, apps (and yet more libraries).
What all this gives you is choice - if you don't like Linuxfeeble you can migrate to WonderLinux without abandoning linux. Maybe this is more choice than you can handle, but it is choice. And, if you can't handle that much choice, just choose a popular distribution and stop worrying.
Its also more transparent; if you think that a particular GUI stinks (and I can't think of one that does; I can think of ones that I'm not comfortable with, but not ones that actually stink, but maybe I'd get more hardline if I was forced to live with one that I don't like) you can just avoid it. With a big, monolithic lump like Windows, you can choose Vista. Or not. Vista gets security fixes, I'm not sure where MS is on its vacillation with support on XP, but it can make a commercial decision to cut off support to older versions at any time.
"Linux" can't do this. A big distribution could drop support for something older, but you can find smaller distros which still support olders kernels, and even if they didn't, you could do it youself. Maybe if the world was full of like-minded individuals, there would be a business there...
And Linux distros are ready to get things done. With Windows you get an OS. With Linux distros, you get enough to actually do something rather than a framework that would allow you to buy things that could let you do stuff. Sometime you might find this wacky (specialist firewall distros, specialist NAS distros, specialist security distros if they are not your thing), but someone has that problem and for them it can be a lifesaver. For the rest of us, a word processors, spreadsheets, mind mappers rss feed readers are the very stuff of life. Err, as are DNS servers, caching programs and networking utilities.