That might work, except she is not using a Dell; she is using a compaq.
The Bios is pretty different, but I am sure the last method would work, but that relies on her parents even logging onto her computer. Still she should try all 3.
If those do not work, here is another method:
1) download this key logger:
http://download.cnet.com/Free-KGB-Key-L ... 57898.html
2) install the keylogger
3) turn on the keylogger
4) convince your parents to type in the password for a site or something "for school"
5) open the keylogger's history and the password should be in the most recent logs