minimal notebook for surfing and itunes that has wifi. It's for a 12 year old...

[Capricious1]

...girl. Mac or PC? What is the minimal amount. I connect broadband via wifi, so I need that built in. Just a CD and ability to connect external drive if no CD/DVD. HD needs to be enough for OS and a little music and pictures, but they are not required. She just goes to facebook and surfs. I want something that won't be slow because of the computer but because I have a 1.5 internet broadband connection. She will use it at coffee houses and bookstores.