I believe you all are over thinking this, I have the same exact dell, had the same problem after installing windows 7. All you have to do is:
1. Download drivers
2. After download right click on downloaded file, click on properties
3. Navigate to the tab that says "compatibility"
4. Where it says "Compatibility mode" select that box and make sure it is set to "Windows XP (Service Pack 3)
5. Click "OK", now proceed to install and it will work fine
*****You have to do this with all of the drivers, but it works on all of them.