The DVD-5 versions were made by Chewtobacca. They are designed to fit on DVD-5 discs (i.e. single-layered) and play in a standalone DVD player. Two of the films are available on Usenet in this format: SW v2.7 and ROTJ v2.5. They can be found by searching for chewtobacca on the NZBKing search engine. I’m not sure how to get hold of the DVD-5 version of ESB v2.0 any more, now that most of Harmy’s links on Uloz are sadly broken.
If you want discs which will play in a PC DVD player (as opposed to a standalone DVD player), then a better option is to go for the AVCHD versions. These are about 8 GB in size and designed to fit on DVD-9 discs (i.e. dual-layered). With the video in 720p and of almost the same quality as the larger 20 GB MKV files, they are a great compromise. Most well-known PC video software (e.g. VLC) will play AVCHDs burned on DVD-9 discs fine, as will most standalone Blu-ray players. But standalone DVD players will not usually read these discs at all.
The AVCHD versions of all three films are available on Usenet. Try searching for despecialized avchd on NZBKing.