Aenima has a lot of songs that are my favorites, but it has a few weaker ones, in my opinion. Lateralus is maybe one song too long too, but I guess overall it's more cohesive and strong.
Opiate is nice, but Hush is the dumbest song ever so it loses all its points on that. I haven't listened to Undertow enough to get a good feel of it, though Sober and Swamp Song are favorites.