From your first post, your dad already has a stand-alone dvd recorder? Does it have hdd (hard disk drive)? If so he could do a lot of simple editting on that. Does his dvdr (dvd recorder) have dv input? If not, there is no great reason to limit yourself to a mini-dv camera, just be sure the camcorder has s-video out, whether Hi-8 or mini-dv.
In comparisons we have made, there is considerable difference between video input to our dvdr and s-video. Some on the DVD-RECORDER section would contest this. Video is not that bad, just that we've found s-video better, brighter, sharper. The difference between s-video and dv input was almost undetectable. We were using a 15" HDTV.
DVD quality? Look at the numbers: Standard tv displays about 240 lines per inch, VHS and 8mm tape store at about 270 lines per inch, S-VHS and Hi-8 about 400, and dv 500 lines and up.
DV (firewire) Carries audio as well as video, but I wouldn't attach much importance to dv just for that reason.
We saw more difference between a single ccd digital and 3-ccd digital than between an older Hi-8 and single ccd digital.
As for a camcorder that records directly to dvd, still pretty new, (never buy the .0 version of anything), you're joining the high-price club, and how would you make copies? The life expectancy of dvd's is an unkown, some failing in just a few years, so tape would be the archive medium of choice for anything you want to keep.
Some of the newer technology is pretty good. Have fun. Good luck.