Is it possible to get back Windows 8 after I wiped hard drive and installed Ubuntu?

So at first i hated windows 8 to the core: slow startup times, tablet-like interface, emphasis on being so simple and "un-technological" that an 80 year old guy could use it, ect. I couldn't wait until Windows 8.1 fixed the problems so i had to adopt a faster OS for free which would be the Lunux distroBut i failed to conduct any research about supported software/hardware on the Ubuntu distrobution of linux and was left with an operating system that was unable to play like 80% of my games and also it did not have iTunes and that's a problem because i have an iPhone. So do you guys know of any means for me to get back windows 8? I don't intend on keeping Ubuntu and would prefer to wipe my hard drive again. I only have random school stuff but i don't need or want any of it anymore. So is it possible to re-download a windows 8 iso legally/legitimately? Will i need a blank disk or usb drive? Which is better? I still have all of the documentation like instruction manuels and stuff. I also have a small grey sticker on the back of my laptop with the windows 8 logo and the words "Windows 8®" colored pink. If i bring the laptop back to Office depot where i bought it from and tell them what happened, are they allowed to give me a fresh install?

It used to be that when you bought a computer it came with a Windows installation disk and perhaps another disk with drivers for the computer. Then there was a period when you got a special Windows installation disk that would work just for that computer, with a version of Windows as if it was already installed. That might have come with your computer, or you might be able to order it from the manufacturer.

But these days, hard drive space is so cheap, there's usually a hidden partition on your disk that has the Windows installation 'ISO' on it. You hit a function key while the computer is starting up, and it boots from this other partition, and asks you if you want to re-install Windows. If you do that, the computer is 'reset' to exactly how it came new.

It don't work like that unless you kept a copy of windows 8 on a usb or another hard drive and you wiped windows 8. Then only way you will get it back is to buy it. Nobody will reinstall it for free.

You can download the ISO of Win 8 from here, http://www.neowin.net/news/here-is-how-to-get-the-windows-81-iso-and-create-a-usb-install-stick

It is legal because it is the activation key that you buy and you can use the one on the sticker on your PC. If it's a laptop the sticker is usually UNDER the battery.