Just to add my piece...
TV/videos/DVDs are often not recommend for children under the age of two due to the effect the quick colourful movements have on children's brain development. Their brains do not work at the speed that images flash and move on the screens causing issues/problems. It is not necessarily the content that is harmful but the movement on screen.

From a website.....
A study from the American Academy of Pediatrics shows that watching videos as a toddler may lead to Attention Deficit Hyperactivity Disorder (ADHD, also called ADD in UK) in later life.

TV watching "rewires" an infant’s brain, says Dr. Dimitri A. Christakis lead researcher and director of the Child Health Institute at Children’s Hospital and Regional Medical Center, Seattle, Wash. The damage shows up at age 7 when children have difficulty paying attention in school.

"In contrast to the way real life unfolds and is experienced by young children, the pace of TV is greatly sped up." says Christakis. His research appears in the April 2004 issue of Pediatrics. Quick scene shifts of video images become "normal," to a baby "when in fact, it’s decidedly not normal or natural." Christakis says. Exposing a baby’s developing brain to videos may overstimulate it, causing permanent changes in developing neural pathways.

"Also in question is whether the insistent noise of television in the home may interfere with the development of ‘inner speech’ by which a child learns to think through problems and plans and restrain impulsive responding," wrote Jane Healy, psychologist and child brain expert in the magazine’s commentary.

Babies brains grow rapidly

Even a child playing with its own fingers has the neural patterning that comes from bending, flexing, stretching and grasping. Scientists tell us that the brain develops in completely unique ways between birth and three years. As a kiddie viddie baby sits "mesmerized", neural paths are not being created. This is crucial brain development that stops by age three.

"You don’t want to think that something as innocent as half-an-hour’s peace and quiet could reduce your kid’s chances later in life," says Claire Eaton, 27-year-old mother from Lewisham, Australia.

I am just putting the other side forward, not for anyone to take personally as any sort of criticism. I firmly believe in parents doing what they want and think is right for their own child.