Not really old - But both Inception and Shutter Island, mainly due to the fact that I can't stand Leonardo DiCaprio.
I feel the same, but I have watched Inception. Well I endured it for 1 1/2 hours then I switched it off. Believe me you are missing nothing with that film, I will not watch Shutter Island now though for the same reason as you.
Films I have never seen:
Once Upon A Time In America
The Godfather 1 & 2
Apocalypse Now
Casino
I have watched all 3 of the Lord Of The Rings films, I think that it was because of the hype or I was maybe hoping that they would maybe stop being such long bore"fests". But alas it never happened. I have no intention to ever repeat the experience though. I have never watched any of that Harry Potter stuff because my daughter is to young...thankfully.