Dora the Explorer is pretty bad. I have a cousin whose 4-year-old daughter is obsessed with Dora the Explorer. I know it's supposed to teach kids Spanish, but it's guilty of the "viewers are morons" thing by repeating everything loudly. Plus the "villain", Swiper, is a total joke. All he does is throw things that he steals into some bushes. Disney markets stuff to kids that age and at least their villains are real villains! It's very repetitive too. I admit the animation is good and at least it's somewhat educational (unlike Caillou, which revolves around a 4-year-old throwing tantrums).
Plus the merchandise is everywhere. My cousin's daughter has a talking Dora doll that never shuts up! Once I tried throwing its batteries in the garbage. I especially hated when they made the older "tween" Dora the Explorer. It was just awful - they turned Dora from a world explorer to a mall explorer. We don't need Dora to discover the mall - aren't there enough Dora products at the local mall?