I wouldn't think about replacement software for the apps you mentioned at the moment. Your first concern will be to get all tv functionality and the other stuff working.
You have one chance for that: http://rivatv.sourceforge.net
Rivatv is a project that is developing stuff to get tvin and tvtuner stuff working on linux. Not sure if the stuff on your card is already supported, if not you really should contact the rivatv developers. I'm sure it is not that hard to add support. (perhaps parts are already supported)
After that there will be various tools to use the features of the card. (xawtv and lots of others for tv / tvin stuff, xine/mplayer for DVD's ..)