Even though technically you SHOULD get a better picture when using the DV input on one of these recorders, in practice it's likely to only look "slightly" better than just using S-Video. This is because none of these DVD recorders can record the straight DV data stream, and it must be converted to the recorder's MPEG-2 format.
Now I haven't tested these side-by-side, so I'm not the ultimate authority in this area by any means, but I think since you're dealing with DV images that originated in a consumer device (ie: the quality of the original is not all that taxing), you would PROBABLY be perfectly satisfied with a non-DV equipped model, such as the Panasonic DMR-E80H.
As for the NTSC/PAL issue, as far as I know, none of these recorders will make PAL recordings. I've had three different Panasonic recorders, and none of them have that option.