First OS?

DropTherapy

I remember using windows XP when I was 8.
There was also a windows 98 computer, but I never used it.
(I apologize in advance for bumping)

Extreme2810

The first time I have used computer it had IBM PC-DOS but first computer I have bought had Windows 2000 Professional

ilovedogs033

This will sound crazy but the first OS I ever used was Windows Vista. But, then again I'm not even 13 yet.

And unlike others, I used it until 2013 and Loved it!

xSuperSeed

Windows NT 3.1 Beta (Forgot what one) (Even Though im 13)

AwesomeWindowsTV

Windows XP on my dads computer, which is now mine.

kgvelkov

Windows XP (for a short time, then I got Windows 7)