Rugrats and Ahh! Real Monsters were-no ARE the shit.
I can't really remember cartoons I disliked because, well, I didn't watch them. I do agree on Rocket Power.
Oh, and Disneys ass raping of Doug really pissed me off. And while this show came out as I was hitting puberty, I still think it counts. Invader Zim. Hate, hate, HATE that fucking show. The stupid Hot Topic/Scene/Indie/Goth/Hipster following it garnered made me hate it ever more. I should love it. It's dark, twisted and has random humor. But its just too random for its own good.
Oh, I hated Ed, Edd, and Eddy and Angry Beavers as well.