WEP is worthless. Don't use it.

Is WEP wireless security better than no security at all? Probably, but not by much. Don't use WEP for Wi-Fi security, researchers say. It will prevent casual crackers from hacking into your network as they drive by, but if they stop for a traffic light, or to roll down the window and point the Pringles can at your WiFi router, they are in.

Instead, use WPA security to encrypt your wireless traffic. For details, see my post on How To Secure a WiFi Router for the Best Wireless Security. To better understand what all the letters & numbers mean (WPA, WEP, PSK, 802.11b, etc.), see Keith's post on 802.11 Alphabet Soup.