My son has been playing D&D with me since he was 6. His favorite part is the miniatures. When we're not playing D&D, he loves to take all of the miniatures and dungeon times and create epic battles using 50+ miniatures. Perhaps that's a draw for your daughter as well.
There are some simpler, kid-oriented RPGs. The simplest is a Pokemon one that's long out of print, but it comes in a aqua-colored box that's about 6x3x2 inches that you should be able to find on eBay (it's not billed as an RPG, though, but it is). I've played it a few times with my son and his firiends, and it's OK. There are also ones based on other cute things such as fairies (not "Fairy Meat", though!), horses, and so on. There's a free _Dawg: The RPG_ from _Knights of the Dinner Table_ at Kenzer Co. There's also _Critter Commandos_, which is a simple miniature-based RPG based around cartoon characters fighting for a futuristic, interplanetary army against the evil Ratzis (my son and I have played that a bunch of times with other adults).