thecoalman - 5:27 am on Jun 19, 2013 (gmt 0)
The ideal format for archiving is the most original source, it's all downhill from there. If these were from a DV camcorder you want the DV file, if it was DVD camcorder you want the DVD file before it went through any conversion. Whatever the file is on the camcorder is the file you want to archive.
If these were transfers from VHS DVD is not a very good choice. VHS is typically noisy and since they are home videos it's probably hand held so there is lot of movement. That noise and movement taxes the encoder resulting in lower quality video than if you had used something like DV which is very lightly compressed or Huffy which is uncompressed.
If you've already burned that bridge, DVD uses MPEG2. There is a tool called VOB2MPG that will eliminate all the DVD stuff and produce a single video file. If you only have these on DVD I'd strongly suggest using VOB2MPG to rip a copy and store on disk. Burned DVD's will fail, the when depends on a lot like the quality of the disc which varies widely. It might be 30 years from now or might be tomorrow but they will fail.
As far as the conversion to other formats go the single biggest mistake people make is not using the source for new conversions. For example:
DV >> 8000kbps MPEG2 = Good method
DV >> 4000kpbs MPEG2 = Good method
DV >> 8000kbps MPEG2 >> 4000kpbs MPEG2 = Very bad method
That intermediate conversion can have very dramatic effect on the quality.