Desktop to laptop

Okay I have a Compaq Laptop Vista Basic. I also have a Windows 7 Hp desktop.
Now the thing is my Laptop is connected to my wireless router and I am trying to connect both via Ethernet. The thing is that they wont connect. I have already uninstalled the NIC local connection drivers on both and nothing. On the Windows 7 it will work for a little bit and say that the cable is unplugged which it aint. I've tried everything can someone please help me. My Xbox 360 works fine and I have already tried 3 new Ethernet cable and nothing. Basically I am trying to connect my desktop to my laptop via the Ethernet cable but, nothing seems to work I would appreciate any help.