Sure ratings have been embedded in television programs for a while now, but TiVo has realized that most parents can't figure out the rating schemes, and end up not doing anything. Or, more likely, they resort to enlisting their child to set up the show lock-out system, benefiting merely the kids by giving them complete control over the viewing habits of their parents. So TiVo plans to fix all that with a new system called KidZone that relies on two groups promoting family programming, Common Sense Media and the Parents Television Council, to pick which shows are cool for the child's age range, and locking out the rest. You can also set up a custom list of shows, or modify the suggested lists, but all of this still hinges on a password, so TiVo had better make the instructions plenty clear for those among the parenting masses who never learned how to program a VCR clock. KidZone will roll out as a free software update in June.