Can only speak on the ones I've read:
Harry Potter (of course)
Hunger Games
Percy Jackson series
Eragon (Yes to the max. I saw the movie first and thought it was bad, my brother told me to read the book and I'm glad I did)
Golden Compass series
Leven Thumps series
Wicked Lovely (think it's a series, but I didn't read other books)
Fablehaven
Ink Heart series (movie broke my heart)
Chronicles of Faeries series
Down the Rabbit Hole (Echo Falls Mystery series)
A Series of Unfortunate Events
A Great and Terrible Beauty
Anne of Green Gables series
A Nothern Light
Chronicles of Narnia
Pendragon series (love)
Cat Royal series
The Door Within Trilogy (ending made me so mad, but I enjoyed the journey)
Fallen (think it's a series too, but only read the first book)
Forest of Hands and Teeth (mood dampener)
An Old Fashioned Girl
Eight Cousins
Rose in Bloom
Changeling (by Delia Sherman. This might be in children's lit now that I think about it. Still a fun book for a any age.)
Pirates! (by Celia Reese)
A Stolen Life (by Jane Louise Curry)
Song of the Lioness series
Protector of the Small series
Trickster series
Beka Cooper series
Nancy Drew series
Hardy Boys series
Singer of all Songs
This is all I can remember right now. Most of these can be cut as I don't think they're the best of this category. I just remember enjoying them at the time I read 'em.
A couple of series I wanted to read but never got to:
Artemis Fowl (heard good things about it)
Ender's Game
Lord of the Flies
Lord of the Rings (saw every last movie, but haven't got to the books)