Will a better graphics/video card improve the quality of videos and DVDs when watched on a computer?
Graphics card: most likely not unless your current video card is archaically ancient (or you have aged older than the Pentium 3 era), since all dvd video playback is done by software (vice hardware) converters Sound card: may improve over onboard solutions for extra connectors such as coaxial or S/PDIF for digital 5.1 or greater support, but that’s another beast altogether.