KBMAN, whether S-Video is better than composite video out of the Laserdisc player is something you may have to test. The video signal on the laserdisc is based on samplings from a composite video signal, so when the video signal is reconstructed from reading the disc it is a composite video signal, complete with color information being modulated on a subcarrier that is combined with the luma, blanking and sync signals. (The color + video (luma or monochrome brightness), blanking and sync is why the composite video port on the converter box that PooperScooper linked to is labeled CVBS.) That means the output port that most accurately represents the video on the disc is the
composite video port.
The S-Video from the laserdisc player is derived from splitting the color information from the luma, blanking and sync signals, a process that isn't perfect since the color subcarrier intrudes upon the finer detail of the luma, resulting in what looks like small hashmarks, but filtering those out result in a loss of detail in the picture. So you may have to do some testing to see if the laserdisc player does the best separation and filtering (use the S-Video from the player to the next device or to the projector), or if the converter box that PooperScooper linked to does the best job (composite from laserdisc player to the converter box), or if the display device does the best job (composite from laserdisc to the projector). Also, since the color modulation scheme is NTSC, which some technicians have dubbed, Never Twice Same Color, don't be surprised if some tweaking of the display device may be needed to produce the best colors for the specific laserdisc player.
Upscaling is also an area where different devices might do a better or worse job, so again some testing may be involved and it wouldn't be too big of a surprise if one can get perfect upscaling or the best detail without color subcarrier interference but possibly not be able to get both at the same time. (One might explore the possibility of a video processor, which has a separate forum, if you don't get an acceptable picture after your testing and you decide you are willing to part with some of your money.)
DVD players are a completely different story: the video information on the DVD (and Blu-ray) is stored as YCbCr (digital component video, equivalent of YPbPr analog component video), so with a DVD player it makes perfect sense to use
HDMI output if available so the signal remains digital from the DVD player to the display device; but lacking that, use YPbPr (analog
component video, and a bit of luma or color information could be distorted by the D/A & A/D conversions),
S-Video (adds more possibility of color distortions), or lastly
composite video (with the addition of the color subcarrier intruding on the fine detail of the picture). Of course, like other media, the image will never be better than the source material, and I have watched a few DVDs that very faithfully had captured the flaws from the video tapes or quite old film stock that were used as the image source.
Too bad the theatrical releases of the first three Star Wars movies (Episodes IV-VI) were never released on Blu-ray, but only the "improved"

versions. That's the biggest disappointment I have with the six-movie Blu-ray set I purchased (and, yes, I knew I was getting the "improved" versions).