You mean 'definitely' the worst....I think.
And TPM is definitely the worst. Worst design, worst story, worst characters (except for Maul), worst kid actor, and worst sidekick.
No I don't mean that.
Worst design? Not very accurate. This is a visit into a new world of Star Wars and I think the worlds are amazing. Naboo and it's ships including Gungans and Otoh Gunga (yes, the characters are annoying but has nothing to do with design). Droidekas, control ships, battle droids, AATs, Sith Infiltrator, Darth Maul, Podracers, etc.
Worst story? It's actually not if you think about it. It's all part of the overall story of discovering Anakin all while introducing us to this new time period. It does need to be edited that's for sure but I don't see anything particularly wrong with the story. Things happen that lead to the next event until it resolves itself. That doesn't happen in Attack of the Clones. After Ep1 concluded, the story landscape was still WIDE OPEN. Ep2 and Ep3 is where the mess continued to happen.
Worst characters.... hmm.. It was a bad execution choice of some of them (Boss Nass, Jar Jar, Neimoidians, announcer, Anakin), but Darth Maul, Qui-Gon Jinn, Watto, Queen Amidala, Sio Bibble, Sebulba, Shmi Skywalker, Chancellor Valorum, Senator Palpatine, Obi-Wan Kenobi, etc were all strong.
Worst Characters in Ep2? Where do I start? Anakin, Captain Typho, Jocasta Nu, Zam Wesell, Dexter Jettster, Waitress Droid, Younglings, Kaminoans, Boba Fett, San Hill, Wat Tambor, C-3PO...
Worst kid actors in TPM... yes. Especially "let's go play ball" kid. AOTC only had younglings and Boba Fett and ROTS had that sad little one who gets killed off screen.
Worst Sidekick... kind of a non category if we have a characters. But if we want to do a Ep1 Jar Jar vs Ep2 C-3PO battle, I found C-3PO to be more insulting to the intelligence.