I have Kubuntu on a second older desktop now and using a KVM switch I
can use XP. Vista, Ubuntu or Kubuntu.

I still prefer the clear lines of Ubuntu over the K version though.

Stop me if I'm wrong but that doesn't even address the question of
whether or not he can get his ATI TV Wonder Pro working does it? All
you are saying is not to use Kubuntu, but if it works under Ubuntu it
should work under Kubuntu as it is just a change in interface.

About the TV Wonder...

I know my ATI capture card an ATI AiW Radeon 7500 card will only
function as an XY input not as a v4l input. Try xawtv or some such to
get it working. If it isn't v4l compatible chances are you cannot use
it under Linux with much success.