Tough choice. Buffon or Del Piero. It's really difficult to choose between them, but I guess based on what Buffon has done this season, I'd have to go with him, albeit marginally. Vidal could well become my favorite player one day, but Buffon is someone who has contributed a lot to the team over the years, and I respect that.
In Italy, I'd have to go with Buffon as well (since he is my favorite Juventus player), but since I have to choose a player from another time (not many choices really, since Juve dominate the Azzurri setup), I'm going to go with Cassano.