The safest aircraft would be one parked in the middle of an unused apron, tied down with no power and a fence around it.
In all seriousness, this is not a topic where you can give a specific answer and say "That is the safest airplane for sure!". We have had many discussions (including one other simulanteous one right now) on this topic. There are certain airplanes that have a very low rate of accidents namely the DC9/MD80/90,737,727,A320,757,767,SAAB 340 etc. The Il-86 also has a good case having over 100 aircraft flying for over 20 years with no accidents yet.
There are others that are not as good, being the A310,747,DC10,MD11. But the numbers for these a/c are still very low.
Future_pilot, please justify your choice of the A330. I would love to see some numbers.