Kubuntu wireless network problem

Hi everyone. I'm having trouble connecting Kubuntu 7.1 to my wireless network. When I use Knetwork manager, I click on my home network, then type in the WEP key, then it tries to connect and it goes up to 28% most of the time then stops and fails to connect, and a couple of times its gone up to 57% and failed. I've also tried playing around with in manual configuration with no luck. I tried using Wlassistant, but that also fails to connect. I have a Linksys WUSB54G adapter and a linksys WAP54 router. I can connect fine to my router with Windows, and MAC filtering is off.

Thanks in advance!

P.S I've just started using linux, so please make your responses easy for a noob to understand :p

Oh and sorry about the double post!