Presently, Windows Vista family drivers (which use NDIS version 6) are not supported by Ubuntu using the ndiswrapper software. The particular WiFi solution that I have has a buggy native Linux driver, and, as far as I can tell, no pre-Vista drivers at all (this card is OEM for HP workstations).
Information on the card itself, though not directly relevant, can be found in bug 104382 if needed.
In any case, when an attempt is made to install the Vista driver, ndiswrapper complains of unknown symbols. The driver is an NDIS 6 driver, which is unsupported at present. Without having a pre-Vista driver available for this hardware, I am kind of stuck either running Windows Vista or putting up with intermittent and horribly slow functionality under Linux. While I would rather do the latter, the current lack of functionality prevents me from doing a lot of things (such as regularly scheduled rsync backups to my in-house server and printing on the LAN). Of course, I can do these things if I move the computer to an area with wires and use the wired connection.
I will be attaching the list of unknown symbols reported by ndiswrapper; hopefully, they can be of some assistance in finding out how to make them work.