OK, first some comments on others mentioned previously, then my recommendations.
McCaffrey - this is scifi, pure and simple, including the Pern books. Likewise (as far as I know) all the Bradley and Robinson books.
Harry Potter- I was surprised at how good this series actually was (I read it recently, and I am 46). I found two of the books "excellent", and all of the others "very good". However, it does *not* quite measure up to any of the great books in my list below.
Shannara - is such a *blatant* plagiarism of Tolkien that I cannot find it in my heart to give this an "excellent" rating, *particularly* the first book. Nevertheless, these first three books *are* pretty well-written, with great attention to illustrative writing that is one of the hallmarks of most (but not all) great fantasy. So, Shannara would definitely not be in my list of "best", but it would be close behind. I am currently re-reading the first 3 books for a review.
His Dark Materials aka Golden Compass - definitely does *not* enter into the list of great fantasy books. I recently read this and have only to polish my reviews before publishing.
EarthSea - you can read my reviews at the link below, like "Materials", does not measure up to the greats.
Dune - not only is this soundly scifi, it is not very *good* scifi.
http://www.life-after-harry-potter.com
Included is a list of only the best sorcery fantasy books, grade reading level, a short review of each book along with a brief summary of adult content. There is also a "Readers' Choice" list of favorite books, and a list of heroine sorcery fantasy books, plus a brand-new original fan fiction.
From what you have said, you definitely need to read the following, in order of greatness and respect as classics. Most are in my list in the link above, but some (labeled NM) have No Magic and so are not included in this list.
"The Sword in the Stone"
"The Once and Future King"
author Steinbeck (replaces Mallory, which can be quite difficult to read, but Steinbeck is only nearly complete)
author Burton
"The Mabinogion" - early Welsh myths, including what is probably the earliest Arthur tales, predating French influence (no Lancelot or Galahad)
"The Jungle Books" - (NM) these are deservedly known as true classics of fantasy
"Dracula" - (NM?) free online, truly excellent and truly a classic. Warning - starts out *very* slowly.
"King Solomon's Mines" - (NM?) think, "Indiana Jones" about 80 years before Indiana Jones was ever imagined. Only "very good", but *nearly* excellent and *definitely* a classic of adventure fantasy (I would say "the* classic).
"Tarzan of the Apes" - (NM) this first book of the enormous series is free online, and unlike any of the movies. Only "very good", but without doubt a classic.
"Tales of the Dying Earth" - despite the amazing excellence of 3 of the 4 books in this omnibus, it rates this far down on the list because it is *not* widely recognized as a classic (too recent). These stories were the foundation for the magic system used by Dungeons and Dragons.
author Donaldson - fantastic story, amazing writing style, in which the hero is *not* on the "side of the angels".
I hope this helps.
Jim