Hi imseen,
I would suggest you to run the Windows Troubleshooter. Right click on the network icon in the taskbar and click ‘Troubleshoot Problems’. Please remove all the wireless profiles and create a new profile. You may refer to the link: http://bit.ly/10dZEFI.
You may completely uninstall the wireless drivers from the device manager and then reinstall the latest drivers from Dell support website. Please paste screenshot of device manager with ‘Network Adapters’ expended.
Keep me posted with the information. I will be glad to assist further.