Optiplex GX270 with Vista. But no ethernet, audio or video.

A couple of months ago I bought a Dell Optilex GX270 with 32 bit version of Windows Vista off someone else.  I turned it on after I connected it to my router and get an error message telling me that the computer doesn't have the devices for audio, video and network adapter.  There are no drivers on the dell site for Vista and I was hoping to get XP reinstalled by calling Microsoft.  Since it was an OEM copy of XP from Dell I couldn't get it, but they tried to convince me to get Windows 7 for it.  Even if I do wouldn't I still have the same driver problems?