About linux

Hi,

Can you say me what is the best linux os ?
I mean like Centos, Debian, Ubuntu etc..

Well, the best linux probably is, which you understand the most, and since you are new, I would suggest Debian. :D

I use Debian to :)

I think CentOS is for advanced users, but Debian is great for newbies :).

I think you mean what Linux distro would be best, as Linux is the kernel and the OS is Unix-Like.
If you're new Hard Float Debian would be a good start or maybe elementaryOS.
The majority of *ubuntu distributions are simplistic and easy to use, Ubuntu 13.04 is notably the easiest to get used to and has better game support (wine).

What version of Debian ?

Debian Wheezy (7)

Or Debian Squeeze (6)