How do I connect Ubuntu to my wireless router?

I have been trying to get Ubuntu to connect to the internet. I have used a variety of websites, and nothing has worked. I have Ubuntu installed inside of Windows 7, and Win 7 works fine on the internet. How can I make Ubuntu connect to my wireless router?
http://www.ubuntu.com/GetUbuntu/download
This is where I downloaded my Ubuntu from. I don’t think it is any special type, just generic Ubuntu. If there is a different version of Ubuntu that works better with wireless cards, and can be installed inside Windows, I would appreciate a link.