i dont quite get what u mean by this sentence, when u replied to my first time
".....where the router uses the ISP's gateway to connect to the internet"
what do u mean by 'gateway'?
u have said that its not possible for them to hack into my laptop system , but what if that person had my wireless IP ADDRESS? could they do anything like send me a virus or spyware or whatever onto my laptop and through that way gain my personal details?