The first three are the ones he wrote, and you heard great things because they are indeed great. 40YOV was pretty good, but not for everyone.
As for the others, he simply had his hands in. Anchorman and TN are just Will Ferrell centered, totally ridiculous humor, that definitely isn't for everyone. I enjoyed it but could understand how some wouldn't. And the others... well you have to start somewhere and he was just a producer.
Freaks and Geeks is classic, and Knocked Up was fantastic. Superbad is going to be real good.