the ISP won't be dealing with his router.. ISPs normally just hand out modems. If it is indeed your own wireless router you are trying to get on sir, ask the person that set it up like your parents for instance. If they don't know then it will get a bit touchier and harder for ya. Grats on the laptop!
mine is a trendnet, and i can get into it via typing 192.168.2.5 on firefox. its the 4th device on my router hence the .5; as it could be .1 or any other ip.
trendnet uses the default user-name / password admin/admin some routers use 1234, or 0123. this always should be changed. if it does not have the default password. your need to reset it. as always goto the makers website and get the exact details.