Outputs. If you think you may want to be able to plug your portable DVD player into your regular home entertainment system, look for quality outputs such as an S-Video for video and Optical Out for audio.
RCA cables are included in the Wii box, but if you have an LCD or Plasma TV, then you will get a better picture if you purchase the s-video cable or the component cable.
The PlayStation Portable contains an AV-out (with the exception of the PSP 1000) that supports composite video, component video and S-video.
Most HDTVs nowdays offer at least three HDMI/HDTV-component ports and at least two RCA ports with or without S-video.
RCA video or S-video in/out plugs also come with the card for easy setup.