First of all, this isn't the correct place to ask this. I would recommend UbuntuForums or AskUbuntu.
Second of all, if your PC has a Broadcom wireless card it won't work without some driver replacement. Plug it up to a wired network, or USB thether your phone. I can't remember the exact commands, but you have to use the terminal to remove the stock WiFi drivers (sudo apt-get remove something) and then install some 3rd party drivers (sudo apt-get install something). My Dell PC has had this problem ever since 11.04, and this fixes it.
Use Google to find the exact commands.
Sent from my Ecliptic DNA
Unlocked Bootloader > S-off > TWRP > crpalmer's Kernel > crDroid