I've never read the high fantasy novel Lord of the Rings, though I've seen the movies a few times.  Do you think it's worth it for me to read them?
I think it is! They are very popular. So many people love them. 
Is the writing at all similar to the Hobbit, the classic children's book?
I think it would be very similar but I cannot say for sure. It is very long, though so you will want to commit to it. If you really liked the movie, I think it will be worthwhile. 
It's probably worth it, since so many people like it.  I know it's sold over 150 million copies, so it must be good :P