What does Restore from this backup mean on iTunes?

So I've got an iPhone 4, and I've music on that but now I want to put that music on my iPad mini. This is the first time I've linked this iPad to my laptop and i can't do anything before I choose which option: either Set up as new iPad OR Restore from this backup (referring to my iPhone).
Thing is, is this something to do with the software? Because of the new iOS.7, I'm not putting that software on my iPhone because of other people that have complained it's wrecked their iPhone 4's. However, I've got that software on my iPad because it's new.
Which one should I select? All I want to do it put music on my iPad as well.

Added (1). My iPad had no music, no nothing on it. I chose Restore etc before the first person answered, and my iPad's fine. It's just got all the music I want on there:)

You can't restore from backup until your content is in I tunes for the iPad. You have to sync your I pad to iTunes separate to iPhone. Choose set up as new and iTunes will do the rest,

You should of really synced up with iTunes before doing anything on your iPad. No matter what option you chose it will erase all that is on your iPad. If i was you i would select set up as new iPad and then when it syncs re download everything and sync it again to copy those apps ect over to iTunes.