connecting to the internet with ibook A1007

I was given an ibook A1007. The person who gave it to me doesn't know anything about it, as it was given to her by someone else and she never used it. It turns on fine, and programs are working, but i want to connect to the internet. I have wi fi in my house. I believe the computer has an airport card but I'm not sure. It detects our wireless connection, but when I try to connect, it says I have the wrong password. I know it is the right password, which is what I use on my dell laptop. Is the problem really with recognizing my password, or is the problem with the airport card?