Cannot Enable wifi in ubuntu 8.1
 

Hi ,I am complete newbie to Linux and it has just been a few days since I have started using Linux and I really love it.
I have a problem that I cannot connect to my Wifi network but I can connect to wired network.I have tried disabling and enabling (System<Administration<Hardware Devices)the Broadcom STA wireless Driver but when I go to network manager I am only able to connect with wired Network and not wireless network .I have Dell Vostro 1520.
I hope you guys help me out because for a newbie I really need this help.

Thanking you

I have a Dell mini 9 which came with a Broadcom wireless card. I used Ubuntu 8.10 on it for a while. The Broadcom STA wireless Driver worked on it sometimes but when I upgraded to Ubuntu 9.04 it wouldn't work at all. I fixed the problem by spending £15 on an atheros wifi card. Atheros cards have much better linux support. They work well with the in kernel driver, no closed source firmware or drivers required. Avoid Broadcrap