couch potato

So, we all hear all the time about how kids watch too much tv and don't get enough exercise and don't use their imaginations enough, etc. Until lately, N. never watched tv unless we were watching something together. However, recently, she found this dvd my mom gave me a while ago and asked to watch it. So, I humored her and let her watch it and suddenly, it's like I've opened Pandora's box. She now asks to "watch dt" and specifically, can she "watch the bear" several times a day. Usually, I try to distract her with something else and that will often work. But we've had a few meltdowns over not being able to "watch the bear." And mommy's also discovered that she can grab 30 - 60 minutes of "get something done" time while kiddo is mesmerized by "the bear."
So, what do you think? What do you do with your kids? How much tv is okay? How do you choose what tv is okay? For instance, I'm not particularly fond of "the bear." Several of the episodes the bear is misbehaving and I don't care for how the parent bears handle the misbehavior... However, the time to get a work out in or clean or cook with out "help" from little hands is also quite attractive. Thoughts?