
Here are the issues to consider:
Most standard DVD players we've tested recently provide excellent 480p picture quality to an HDTV. Many new players can also upconvert regular DVDs to pseudo-HD, often with good results. It makes sense to buy one if you need a player and don't want Blu-ray. But if your DVD player is fine, it's questionable. Your TV must have an HDMI input to accept upconverted video.
If you have an LCD or plasma set, it's already upconverting the video from your existing player to match its native screen resolution. A specific player might or might not handle the conversion better than your TV. Buying an upconverting model gives you the option of using whichever device works better.
True high-def images from a Blu-ray disc are inherently superior to video from a standard-definition DVD, even if it has been upconverted. A Blu-ray HD disc contains far more picture data, so images look more detailed and lifelike. You'll see the benefits of a Blu-ray player most on a 1080p HDTV, which can display all the pixels in an image, but a 720p TV can display more detail from a high-def disc than from a standard DVD.
Note that a Blu-ray player can send 1080p high-def signals from a Blu-ray disc only via HDMI. With an older HDTV that lacks such an input, you can connect to the Blu-ray player via a component-video input to get 720p or 1080i HD signals.
All DVD and Blu-ray players support 5.1-channel surround sound (some offer 7.1) and can pass along digital signals. They can also decode the signals and pass the analog output (stereo and sometimes multichannel) to a receiver or TV with analog inputs. Most new Blu-ray players support high-resolution multichannel audio formats such as Dolby TrueHD or DTS-HD Master Audio.
With Blu-ray there are three profiles, each with different features. If you don't need the latest bells and whistles, buying an older Profile 1.0 player can save you money—if you can find one. Willing to spend more? Profile 1.1 models offer BonusView, a PIP feature that displays bonus content on some Blu-ray discs in a window while the main feature is onscreen. Profile 2.0 players add BD-Live, so you can access online content such as movie trailers when playing some Blu-ray discs.
If your TV does not have a built-in digital tuner (ATSC) and it is connected only to an antenna, buy a recorder that contains a digital tuner to receive broadcast TV, after analog broadcasts have ended in your area.
Inquire whether a cable box equipped with DVR functionality is available. If satellite service is an option, consider getting a receiver that includes a DVR.
And some satellite and cable DVRs work only with the service provider's programming and won't record from other sources, such as an antenna.
Then you need a DVD recorder or DVD recorder/hard-drive combo.
Your options right now are an HD-capable DVR that's incorporated into your cable box or satellite receiver, or a TiVo HD DVR.