Well, as much as it sucks, you will NOT be able to use any sniffer (kismet, airsnort etc) with the Broadcom b/g card, trust me I have one in my HP zv5220 laptop and there is no native driver, and the ndiswrapper does not support monitor mode. You can connect to a router with the following commands.
iwconfig [interface] essid [SSID Name]
iwconfig [interface] mode managed
iwconfig [interface] key [full binary WEP key] ##--If applicable
Now on that token, you can pick up a cheap PrismII based 802.11b card for ~$20 and that will work out nicely.