Start afresh or restore??

I have bought my wife the iPhone 5 but at the mo she is using my old 3gs she hasnt really done anything with it, she has a couple of apps and music but lots of photos and videos, the problem is I am not sure what to do with the new phone if I set it up as a new phone can I restore her contacts from iCloud and leave all the stuff she has left behind or will that go on to the new phone too?
Sorry for the long winded post.