It all depends on your personal taste. One thing I would say though is to not sit at the back of the first (I think!) tier in the Tribuna - you're under a roof, and whilst your view of the pitch isn't resricted, your view of the rest of the stadium is, which completely changes the atmosphere.
Personally I like to go the lateral side as close to the half-way line as I can. But apart from under the roof in the tribuna, I've never been disappointed with any seat.