I can see and smell my half sun-faded copy of Andalite Chronicles as soon as you mentioned it. It was my first Animorph book and though I loved them only the Hork-Bajir Chronicles held up.
My next jump was to Mossflower and Redwall!
My next jump was to Mossflower and Redwall!
I've also reread all the Redwall books as an adult and it was amazing. Be aware that they didn't make audiobooks for all the books so if you're planning on listening, you'll have to read at least some of thing in book form.
Also they didn't make hardcovers for everything which is annoying if you're collecting them to sit on a bookshelf.