Windows 7: no connection windows 7

I have a Dell laptop a Inspiron 1720 its about 3 years old and has Windows 7 Ultimate on it. The other night I went to use it and it would not connect to the internet. I did the comand prompt ipconfig /all and it listed many things in the command prompt but they all looked the same and none of them had a IP address. I tried using the troubleshooting and it found nothing. The laptop had been working fine days before. Comcast said I that physical problems with the lap top but I know they really don't have computer savy. I spent hours trying to get it to work. It shows several Wifi connection but as I recall if you plug in your cable direct into the ethernet jack you should be able to connect but I can't I don't even see anything other than Wifi connections. am I missing something? Any Ideas?

Mark,
When you connect with a wire, you should go to control panel, network and sharing center. From there you should see your connection. If you do not, go to the left hand side and click on 'change adapter settings'. What do you see in that window?

Thanks,
Sarah