Linux mint 11 was my main system for a long time. Now I'm about to upgrade to Linux mint 14 MATE and dual boot Windows vista. Short answer: Linux mint is my favorite.

this and that, but xp is my favorite but cant use anymore cuz its so old and incompatible

Windows 7 and any kind of Linux is nice.

Right now desktop win7 and my old laptop is crunchbang. I would put linux on my desktop and say fuck you m$, but linux cbf with games and other cool stuff, so it'll be awhile.

Definitly Windows 7 and 8 Right now its Win8 ;) - Linux is nice too, but for Games etc. its unusable since wine isnt that good.

Ubuntu!

Ubuntu

Gotta say Ubuntu, though I prefer pretty much any linux build. Truthfully, the only thing I care about is the shell since I use it the most, either Bash or C shells and any UI and I'm good. Home PC has windows 7 since Linux has very little game support (though steam seems to be on that problem).

Meh... I don't have any favorites but I do use Windows 7 and Lion on my computers.

My Favorite operating system is Window 8..

Windows 7

Windows 7
Windows 8

i love windows xp,window 7 and mac OS.These are my favorite one.

Windows 7