I have 4 DVD players (yes 4) ...
- Xbox - Good average DVD player. Has zoom, and reasonable FF/RW options. Nothing spectacular, but if you already have an Xbox, the extra $30 is a good deal. Plays DVD-R/-RW and DVD+R/+RW too. (Street Price ~$200)
- PS2 - I have the original US DVD drivers, so perhaps the new ones are improved, but the ones I have are sub-par for a standard DVD player. There is significant problems with the playback quality of movies, especially when dealing with solid colors like in cartoons (solid colors tend to look very grainy). There's hardly any options built into it, except for your very basics Play/Stop/RW/FF... The Sony made remote adds a bunch of features but I don't own it so I can't comment on it. My PS2 can't recognize DVD+RW or DVD-RW (haven't tried any others) but newer PS2's supposedly can. (Street price ~$200)
- Sony DAV-S300 HTIB - Fairly decent DVD player, playback quality is good, DD 5.1 and DTS built in is nice (it is a 1 unit receiver/dvdplayer) ... It doesn't play DVD+RW/DVD-RW though. (Discontinued model)
- JVC S500BK - This is my progressive scan DVD player, playback quality is excellent especially on an HDTV, FF/RW features are abundant, zoom features, etc etc ... what you'd expect in a name brand DVD player. Only problem I've had is that you can't zoom in and watch the DVD because it leaves a stupid zoom icon on the TV showing u how much you're zoomed in. This is especially important when you're watching a Letterboxed (non-Anamorphic) DVD on a 16:9 TV that is improperly marked... If it weren't for the zoom icon, you could zoom out the black bars and get a full 16:9 picture on a widescreen TV. Also plays VCDs (on CD-R even), SVCDs (ditto for CD-Rs), MP3 CD-R discs, and can display JPEGs burned onto a CD. Was compatible with the DVD+RW that I threw in there, haven't tried any other formats yet. (Street price: ~$120-150)
I think you'll find that for the average joe, any "name brand" DVD player like a Toshiba, JVC, Panasonic, Sony, Samsung, or RCA will give you pretty good results on a standard TV for DVDs. When you start stepping up to higher end TVs then the differences between higher end players and lower end players may show up... But DVD for the most part looks good on almost any player. If you need VCD/SVCD or anything else, thats where the differences seem to lie. So just buy one that has the features that you really want.
Hope this helps!