Jules,
Firstly
to CF
Secondly, if you are using an ethernet connection you shouldn't need to use the NTL software anyway! To solve the vtruck problem, read Robin Walker's
notes here.
Firewalls do not normally block browser ports, but if you want to check, see if it's blocking iexplore.exe or port 80 & 443. Is the firewall blocking everything, eg lockdown mode? To test, try 'tracert www.bbc.co.uk' from a dos prompt'
HTH