I cannot connet to Wireless Access Point

I am using Dell Laptop 610C and AzTech USB wireless adapter. When I view the signal I can see up to 20% strength signal. 3 Access Point I can detect. Two of them are protected via WEP and one is open.

The problem is that I cannot connect to even open AP. Further more I would like to capture the packet from these protected (WEP) AP to get WEP Key (password). Is there anyway to break into WEP? I saw lots of video on this topic on YouTube and GoogleVideo, but problem is that if I cannot get connected, how can I capture the packets. I tried some software, it shows the signal strength but could not capture any packets.

Please advice me how to do it? What software to use?

Of course you cannot connect to it, you shouldn't even be allowed to connect to it if they are not networks that you own !

If you do want to learn how to crack WEP, for education purposes of course......

1. Install Ubuntu and learn how to use Linux commands
2. Get a better wireless card
3. install aircrack and read every documentation you can find
4. if you have gotten this far then you should know where to go from here