The endless debate rages on. Which OS do you use? What version? What release? What kernel? Why?
At the end of the day, if your computer does what YOU need it to do, and you’re comfortable with what you have, then I guess you have the “right” OS.
Telling someone that they should be using a different OS is like telling someone what to wear. You can make suggestions, but it shouldn’t go any further than that.
When I talk to Windows users, I like to “suggest” they take a look at Ubuntu, simply because it’s free, they can use a LiveCD to try it without installing it, and it’s a great OS. However, I also suggest people look at Apple when thinking of purchasing a computer, new or used, simply because Mac OS X is an excellent OS, and Apple makes very good hardware.
At the end of the day, all that matters is that you are happy with your computer, and that it does everything you want it to do. After all, isn’t that the point of having a computer in the first place?