You need to remove the prop and find where the oil is originating. Most oil leaks from the prop area of an outboard are simply because of residue oil seeping down the exhaust stack inside the mid section of the outboard leg and then coming out of the prop hub, it's perfectly normal for 2 stroke outboards. Should the oil be seeping out from the drive shaft seal, well yes, it needs to be looked at by a mechanic. A friend of mine, Daniel owns Marine Works in Kirrawee, he will help you. See: http://www.marineworkssydney.com.au/contact/
As for the ding on one blade of your prop, you can post the prop to another friend of mine.. Grant Lundberg at Berry in the Shoalhaven, where I live. He repairs both aluminium and stainless steel props for outboards and then posts them back to the owners. See http://www.lundbergpropellers.com.au/aboutus.html
Have the ding repaired, you will be surprized how much better your boat will rin.