Good question, I cannot give an intelligible answer. I have heard from others that Samsung wouldn't have issue honoring the 5 years, saying that I've only ever known 1 person to have a drive fail and knowing him it wasn't the fault of the drive. You can feel pretty confident with these drives I only wish they'd fit in my ultrabook instead of having to fork out 4 times the price for the new PCI Express format.
It doesn't not come with Windows operating system, none do, its just a solid state drive.
It comes with Samsung software to clone your existing HDD with the current Windows install (windows 7/8) - transfer is seamless and you are not required to active your license again.