On the subject of full episodes, another one of my favorites is "Arthur's Snow Biz; Bugged".
The former features a plot deviced that seems to be used very often on kids' cartoon, but it did put an interesting Arthur twist on it obviously, while the latter was one of those really interesting stories that delves deep into the character's mind, in this case, Brain realizing that his being a know-it-all bugs his friends at time.