The Victorian system of registration is one of the best in the world, there is plenty of useful information on both the certificates and the indexes.
What you'll find on a Victorian certificate of birth, death or marriage:
Births
Date and place of birth; name of child and whether present or not; name of parents (including mother's maiden name); occupation of parents; ages and birthplace of parents; date and place of marriage of parents; previous children of their marriage noting living or deceased; signature, description and address of the person who gave the information; names of witnesses; date and place of registation.
Deaths
Date and place of death; name and surname; occupation of the deceased; sex and age; cause of death, duration of illness, medical attendant by whom certified and when he last saw deceased; name and surname of parents (if known) including mother's maiden surname; signature, description and address of the person who gave the information; signature of deputy registrar, date and where registered, when and where buried, undertaker whom certified; name and religion of Minister, or names of witnesses of burial; place of birth of the deceased and how long he or she resided in the Australian colonies or states (stating which), name of spouse, place of marriage, age at marriage; names and ages of children of the deceased.
Marriages
Date and place of marriage; name and surnames; conjugal condition, whether bachelor or spinster, widow or widower, stating date of decease of former wife or husband; children by each former marriage; birthplace; occupation; age; residence (present and usual); parent's names of each party (including mother's maiden name) and occupation of father; signatures of the parties and witnesses; signature of Minister. Prior to 1963 the date of termination of previous marriages of the parties is also shown.
With a death certificate I may add that the information is only as god as the informants knowledge. If you get a certificate at leastyou get a burial site too.
Jenn