I'll give you a summary of what i see in the question.
To what extent has law reform been effective in dealing with contemporary issues concerning family members
Basically you are choosing a couple of the contemporary issues involving family members out of the syllabus which you have studied and researching law reform relating to that issue and seeing if its effective.
Issues from the syllabus:
•recognition of same-sex relationships
•the changing nature of parental responsibility
•surrogacy and birth technologies
•care and protection of children
If you need an example, lets use the recognition of same-sex relationships.
The Adoption Amendment (Same Sex Couples) 2010 allows same sex couples to adopt. Was it effective? Yes, because it gave same-sex couples the ability to adopt which they did not have.
You could even talk about the Marriage Equality (Same Sex) Act 2013, which was passed in the ACT a while ago. Was it effective? Nope. It gave gay couples the right to marry for about 5 days. Then the high court voided all the marriages and the bill.
This was just an example and IMO you shouldn't pick same-sex relationships but one of the other three since it should involve family members.
Hope this helps and good luck.