We went as a family a couple of times several years ago, we stayed in various small villages but did the decent from Fuente De on both trips. If you get there for the first cable car they will take you and bikes up, then you get an all day decent (almost). Well worth going, but be prepared for some road riding between off road sections, but you get some massive rocky decents with nobody on them. Email if you want more suggestions, I can put you in touch with my dad who acted as our guide after much research, he’s more likely to remember what we did and where as I have a memory like a sieve.
I remember a particular switchback section where al 3 of us were boiling water from camelbacks off discs (old split caliper Hope minis with 160mm rotors) at almost every corner. Great fun and I’d love to go back
Not related to biking but they have great cheeses and cider if that tickles your fancy
Matt