Re: I am guessing you use BT as your ISP
" A tracert even had me getting out of virgins network hanging for 3 attempts then moving to BT onto manchester (where website is hosted) then hanging at the last hop."
That is simply a router that doesn't respond to ICMP (*) but tracert waits anyway until timing out.
Annoying, but not weird, or related to any network issue you have if your trace moves beyond it.
As for your problem, are the MTU values the same? And have you filtered ICMP at the router, so stopping the OS receiving any ICMP 'need defrag' messages from being received?
MTU issues wouldn't affect the traceroute, but the website could be blocking ICMP - Did the tracert succeed on the machine which could connect to the website?
(*) MS tracert defaults to using ICMP probes, unix tracetoute defaults to using UDP