What is the easiest way to save my iTunes library, when I reset my laptop?

I need to reset my laptop because I was an idiot and downloaded many different things that just generally make using my laptop hectic. My only concern is missing my iTunes library. It's on my iPhone but that's it. What's the easiest way to save it then transfer it back once I redone load iTunes etc?

Transfer your music to a flash drive

Copy all the backup folders in iTunes to a flash drive

You could do this:
Go to the location where iTunes is save. For Windows it is under My Music.
Next, right click to the folder and compress the folder. If you have a file archiever use that it will save more space. (7zip is the best in size)
Move the zip/rar/7z file to a flashdrive, Dropbox, GoogleDocs, MediaFire, or whatever. Then when you get your new computer download it and uncompress it. Then put it in your iTunes library after iTunesi s installed.