I have a PVR 350 and a Win-tv dbx card in my myth box, Mythtv seems to work perfectly except for the Video. When I go to watch TV I just get a black screen, also the DVD player in myth dons't work right either (don't know if this could be a related problem or not) When I type lspci -v I see the cards with there name but it says [Disabled] in the description. Any advice?

For the DVD issue, if you are using R5A12, it hardcodes the symlink of /dev/dvd to /dev/hdc. HDC is the master device on IDE channel 1 (not 0). Figure out where your DVD is actually plugged in and change the symlink accordingly. For example, if your DVD is the slave device on IDE0, then do this:

rm /dev/dvd

ln -s /dev/hdb /dev/dvd