From XP and Mandrake to Ubuntu and Vista

My notebook was "KIA'd" in the weekend. I now have a Compaq Presario V3000 Notebook which came with Vista installed. Tonight, I have created allocated a 30 gig partition (total is 160) for the installation of Ubuntu. However, I am hoping to get my wireless connection working. The system is able to roam and identify the network. It just doesn't actually succeed in making an internet connection. Does anyone know of an executable command or the correct file I should be amending to achieve this? I am a newbie with Ubuntu, so your advice would be much appreciated.