What with TV programmng moving to the Internet, you want any new computer to be able to hookup to your TV set. Unless you like watching TV programs on your laptop's screen. Me, I prefer to get my couch potato fix sitting in my recliner in the living room. For this to happen the computer needs to drive a signal down a cable into the TV and both computer and TV need a connection (a port) compatible with each other. There are at least four common types of ports, trouble is, not all computers or TV's come with all four types.
Composite video. This is the single prong RCA type connector (phono plug we used to call them). All VCR's (remember them?) came with a composite video output jack, and all TV's made since the VCR age have one. There aren't all that many TV's still running from pre VCR times. Composite video is pure analog, and works reasonably well. Some but not all computers have composite video outputs.
S-video This has a 5 pin DIN connector, and is less common. But it gives a much nice looking picture than composite video, the colors are clearer and the video is crisper. The presence of a S-video connector on either the computer or the TV is a plus.
VGA A 15 pin three row DB style connector used on computer monitors. Many computers, including laptops, have a VGA output, and new TV sets often have one too. Gives VERY good video.
RGB "Red-Green-Blue" three RCA connectors and three cables DVD players often have RGB outputs. Few computers have them. New TV sets will have RGB inputs. Gives VERY good video.
Bottom line? If shopping for a computer, take a look to see what it has for video outputs. Some laptops have no video out at all, which means you will never be able to use it to show Internet TV on the TV. If your TV has one of the better inputs, like S-Video, or VGA it would be nice if the computer had a matching jack. If all your TV has is composite video input, your want your new computer to have a composite output.
Remember computers get replaced fairly often, and the brand new laptop you buy today, may well be your #2 machine demoted to living room TV watching duties in few years. Remember also that your children will grow dissatisfied with their current laptops, upgrade to something newer to run their games faster, and leave the old laptop with parents. My three children have gifted me with as many castoff laptops. The laptop you buy your child today may be a castoff left at the old family home sooner than you think. It would be nice if said castoff were at least useful for watching TV.