The laserdiscs only had English if I recall correctly, they had a shitload of subtitles for foreign languages though.
I hope you're not planning on including several DD5.1 tracks on the ESB:R because they take up over 300MB per track, which means less space for the actual movie.
Personally I think the best option would simply be to add subtitles, watching these films dubbed does them no justice.
Anyway, welcome back Ady :)