If I remember correctly, this keyboard is backlit. Most likely the copper cable is for the backlit power. A new keyboard would need to be purchased to fix it.

Can you post a picture somewhere and the link here?

A new hard drive normally doesn't have Windows installed on it. Hopefully you have created the dell recovery dvds when you first obtained the laptop. If you don't have that you can try and download the dvd image from Microsoft at http://www.microsoft.com/en-us/software-....

If the connector on the motherboard is still attached and only the clip is broken you can try and find a new clip, or perhaps tape the keyboard in place with electrical tape.

I also broke my wire trying to use tweezers. I should have known better. I use (normally do) a spudger on one side and my fingernail on the other to gently pry these types of connectors out. I ended up buying a replacement faceplate on ebay.