Yarra Valley - MY first choice would be a tasting session at Domaine Chandon (actually I think you may be able to dine there) Sitting in the restaurant with the vines sloping away and the Warburton Ranges in the distance.....absolutely superb - you would not want to live anywhere else but Melbourne! A little down the road is Bella Verdura which is a fabulous Italian restaurant .In Healesville - the Healesville Hotel has super food. Also try Innocent Bystander - a really buzzy spot - wine tasting, lovely food, cheese/deli/bread/pizza, all terrific. If they are older/more conservative, maybe the RACV Country Club for lunch. Seeing native animals at the Sanctuary is always fun.Try the Mornington Peninsula - so many wineries and fab places to eat - Port Phillip Estate, Montalto, Dromana Estate. Flinders Hotel or the Portsea pub both have good food, and the scenery is always lovely. Go stgrawberry or cherry picking at Red Hill. Call in at Heronswood at Dromana, stunning gardens. Point Nepean national park, you can hire bicycles to ride out to the point. Catch the ferry to Queenscliff. In Melbourne, the NGA or Ian Potter, a boat ride up the Yarra, the Museum, the Aquarium, the Zoo - Werribee Park is super fun, do the open plains zoo or the Mansion, lovely rose garden, and you can eat there too. The Botanical Gardens, Williamstown, Lygon Street. It';s always interesting to look at the food available in other cities/countries so I recommend South Melbourne or Prahran market.Try some of the bayside eateries - Donovan's would always be my personal favourite.
Does this help??