wifi issues

i have a dell inspirion laptop that is now having trouble picking up wifi from the wireless card. this all started when we bought a usb wifi antenna to help with reception and installed it. it said it was windows 7 compatiable but picked up less signal than what we already had with the factory built in card. so after uninstalling the wifi antenna software we cannot get the built in to work properly. when i try to do the network diagnostics it says " wireless network adapter is diabled" when i got to change the setting of my network adapter it gives me the options of "disable or connect and a few others..but no where does it say enable. i hit connect and although it shows our network it wont connect..it comes up with these errors "none of the networks previously connected to are in range" network cable is not properly pluged in" and again the wireless network coonection adepter is diabled" i tried a system restore but that has failed when i try to use dates prior to these problems. any input into how i can reset my wifi settings and get things working again? thanks matthew

lucky, thanks much..that did help and it seems to be working ok now:) THANKS