Hi I am looking at getting an old Unibody Macbook, the original one which came out, 13", 2.0GHz, 2GB, 160GB HDD etc and I was wondering how long does the battery last in it? I heard it wasn't that long, can I install the new longer 9-10 hour battery into it? A few other side questions: - Can I put in a bigger HDD? - Can I put in more RAM? Thanks!