Ah, I wish I could help you out more but I haven't messed around with ndiswrapper enough myself. And I've never done anything with a Broadcom card besides my gf's laptop.

I'm thinking right now the issue is the WEP on your router. Can you disable it temporarily to see if you can connect? If so then it's probably the driver you have installed can't connect to encrypted points. In that case the issue can be narrowed down at least.