The Zoomer Races in Jak 2 are pretty bad, so is that god damn rail shooting mission.
Jak 2 is a very difficult game that can get unbelievably frustrating at the drop of a hat (Or throw of a controller)
Those are the parts of the game where I probably threw the most controllers.
Other moments
There's a part of generation 4 of Record of Agarest War where (Spoiler) happens and you need to do 3 really tough boss fights. And if you built your party like I did... you will be fucked royally.
It's a neat concept, and it makes you play differently but if you built your party wrong it could end your progress.
I don't really hate any other parts of my favorite games.