I'd download McAfee' stinger program from another machine, copy to CD or USB key and install on affected chav....ahem laptop.
As it says on their site:
"Stinger is a stand-alone utility used to detect and remove specific viruses. It is not a substitute for full anti-virus protection, but rather a tool to assist administrators and users when dealing with an infected system".
It is possible that "It" has downloaded a torjan which is blocking access to the Net, 'xcept for those sites/urls it wishes to use for nefarious reasons.
hth
amofw