Well Debbie, the entry for James is definitely the correct one - as we do know his parents were William and Loveday.
The entry for Grace Couch I think is connected but I'm not sure how. Her birth year would have been c1776 if she was 60 in 1836. This would make her too old to be James' mother (the individual shown in the 1841 census with parents James & Jane and sibling Elizabeth). We know it's not the mother of James born 1809c but could possibly be William Couch's mother.
The William Henry Couch sounds feesible as a sibling of your Jane from the year of birth - 1836. I'm not certain why he would have been buried with this Grace though. I could understand if this had been Grace, the first wife of James as it could have been William's mother of course.
The entries for William and Albert. Again I'm uncertain about these as so far they have not featured in either the 1841 or 1851 censuses with the same family group as before (ie: James, the head, Jane the wife, Elizabeth and James the children).
Regarding the birth dates, well, I've only managed to find what has shown up on LDS - sometimes the birth dates are shown, sometimes just the Christening dates - however, I have found that there occasions where these are actually the same date!
I will have a look into Albert and Henry to see if I can throw any light on these two and their connection to your Couches.
Sorry I'm not sounding more helpful at this stage.
Kay
Manager