Having Trouble Connecting to the Internet

Hi there,
I am running Parallels for Mac Desktop 4.0.3846, and Mac OS Snow Leopard. I am having trouble connecting to the internet on the Windows side. Last year, when I was running a earlier version of Parallels I was eventually able to connect, by changing various settings (I think I just got lucky). Could someone walk me through connecting to the internet? I am afraid I have changed all settings (Mac OS X Preferences, Windows Settings, and Parallels Network settings) so that I am not able to connect. I connect to the internet via airport on my Mac Side.