Let’s see…
We’ve got Noggin, PBS Kids, and PBS Kids Sprout saved. Your daughter is definitely too old for Sprout, and it barely holds my four-year-old’s attention anymore. But the others will hold your daughter’s attention; the games are challenging enough and the sites are easy to navigate. She may also like some of the cleaner cartoons on Weebl’s Stuff; they’re fun and nonsensical.
I second the suggestion of making the browser’s toolbar all kid-friendly so she’s always got somewhere safe to go. In fact, we’ve got a third profile set up just for Aaron so he can’t get into either grown-up’s and possibly screw something up. His doesn’t have admin privileges so he can’t download anything, and we tend to run anti-spyware programs every so often. But the two sites I’ve linked to haven’t contributed anything like that.
Robin