Hello - Melbourne is a great city and you could actually spend all your 5 days just seeing the sights downtown. May can be very cold so that might limit beach activities somewhat. You should definitely drive to Healesville where there are native animals to see and some great vineyards around however, if you are driving one of you can't do too much tasting! A drive along the Great Ocean Road is one of the best scenic routes in the world and takes you along the coast. there is also a walking track there so get out of the car and take in some of the fresh air. Along the coast to Portsea and lunch at the Portsea Pub - one of the best days you can have outside of Melbourne. There is so much to see and do it's a shame you only have 5 days. There are some very good websites - www.visitvictoria.com www.onlymelbourne.com.au www.melbourne.visitorsbureau.com.au. I do hope you enjoy your vacation.