Installing iTunes

A friend of mine backed up her iPhone through iTunes on her PC and then updated her iPhone 4 on a friend's mac.

She has lost all of her songs and when she plugged her phone into iTunes on her computer, she received a message advising she needs to install iTunes version 10.6.3 or later.

The problem is my friend does not have an internet connection on her pc.

If my friend installs a copy of my iTunes from a USB, will it automatically update her version of iTunes? and if not, what will happen?

Thanks