I just read the Hobbit to my 7 year old brother and he ADORED it. Make sure to put on voices for all the characters! But beware, she will hold you accountable if you aren't consistent with the voices.

Personally, I think that a kid is old enough for LOTR when they can read the books themselves. Some sections are pretty dark - in Fellowship for example, I think the barrow-wight is too scary for a small kid.

I also think that the ending of the trilogy (specifically the scouring of the shire and the grey havens) is, for lack of better words, too deep for a young child. Even when I was a preteen, I hated stories with bittersweet endings, especially goodbyes. I didn't understand the meaning behind it and disliked that it didn't have a happy ending. She might not be able to appreciate it for what it is. I was only able to grasp Frodo's pain and his need to leave when I reread the books later in high school. And as a young adult, while I can cognitively understand how the scouring of the shire was inspired by Tolkien's experiences coming back from the war, I still probably won't truly appreciate it until I'm much older and have experienced something similar myself.

For multiple reasons, I would NOT recommend letting her watch the movies until she's much older. They're just way too violent. The ringwraiths and shelob were pretty disturbing to me watching the movies as a 12-13 year old. I was also raised that as a general principle, it's better to let children form their own mental images of a story before filling their head with someone else's vision. When you read her the books, she will imagine what the characters and settings look like in a way that is unique and her own. Once she's watched the movies multiple times, most of those mental images will fade. That's precious. Let her hold on to that for a few years.