You asked When recording in HD can you use the supplied editing program to record onto a standard dvd for family who may not have a Blu-ray Player,
The answer is I do this all the time.

I use my iMac with the latest iMovie, record in HDV, then edit and then use iDVD to burn standard DVD's for backup and for my family.

I squish the HDV format when downconverting the standard DVD. But if played on a standard DVD and standard width TV everyone looses about 20 pounds. If played on a standard DVD then "stretched" to my wide format TV then it returns to its original dimensions.

I can also choose to letter box or crop the wide format so the width dimensions do not get squished on a standard TV.