In the absence of a R1 edition of Secret Ceremony, I will compare this local DV1 edition with the UK, R2 version released by Universal Home Video in May 2006.
Naturally both are PAL transfers. Although the UK edition is in the correct aspect ratio of 1.85:1, it is not 16x9 enhanced. The UK version is also totally void of extras. At the very least, the local, DV1 edition has the meagre inclusion of the original theatrical trailer.
Although there isn't a lot between these editions, the local DV1 release appears to be the version of choice.