1. Post an ISO, not a bunch of folders. This will not only make sure all the files are in the right place (video in VIDEO_TS, info and covers and other art in DVD_ROM, for example), but will also preserve the name of the volume.
2. RAR it up good.
3. Make about 20% PAR2 files; post 10% immediately following the original post if you don't want to be posting fills for the rest of your natural life.
4. Make an SFV, an NFO, an NZB, and a sample. Make a representative sample file: a piece of menu, say, plus some action? Maybe some subtitled parts? There's nothing quite as frustrating as a sample that's too big (don't need more than 20 seconds) and that doesn't show anything you can make decisions on.
5. Post the NFO as text, or (if you must) as a downloadable NFO. Don't include these little crap files in the PAR2 stuff (which is why I put these things in two separate steps, above).
6. Post the PAR2, SFV, NFO, NZB and sample files first, then all the RARs, and then the first 10% of the PAR2 files.
7. When losers whine about missing some PAR2 files, maybe post a few more.
If these steps are followed, it's virtually impossible for a sane downloader with more than two brain cells to rub together to screw it up.