The Simpsons The Complete Thirteenth Season, the Ralph Wiggum cover, features 22 episodes on 3 Blu-ray discs or 4 DVD. There does not seem to be a major difference between the two versions aside from the fact the disc menus in the Blu-ray version are fancier and more animated. Though season 13, 2001-02, was still Fullscreen you need not pre-adjust your widescreen set.
Season 13 of The Simpsons is on the uneven side. It opened with Treehouse of Horror XII which features the Harry Potter spoof. Other fun episodes on disc 1 are the one where Moe goes back to bartending school and reopens a mod Moe's for a while, and She of Little Faith where Lisa becomes a Buddhist.
Disc 2 opens with Marge trying to cut sugar out of Springfield's diet. This disc also features the Blame It on Lisa Rio de Janeiro episode and Tales From the Public Domain with the Odyssey ("The next time people think wood, they'll think Trojans), Joan of Arc, and Hamlet.
The Simpsons The Complete Season Blu-ray disc 3 includes I Am Furious Yellow where Bart makes a Homer cartoon. Marvel Comics star Stan Lee guest stars and does a decent commentary track. The disc also includes a decent clips episode, and the one where Fat Tony tries to kill Homer after he becomes the law.
Some of the episodes on The Simpsons 13 do not include the Bart writing on the blackboard scene in the opening and the rest of the opening sequence does not look as pristine as in other episodes. Not being a Simpsons expert, I do not know if this means anything.
Special Features on The Simpsons The Complete Thirteenth Season Blu-ray and DVD are: Especially inane audio commentaries on every episode; Deleted scenes; Featurettes: A Token from Matt Groening, Ralphisms, The People Ball, The 13th Crewman, Blame It On The Monkeys, The Games, The Sweet Life of Ralph; Animation Showcases for episodes The Parent Rap and Sweet & Sour Marge; Sketch Galleries; Commercials
Special Languages on some episodes; Easter Eggs
The Simpsons - Bart Wars