I am gonna hand out points out of 10 and average them:
Pixar
Toy Story ----------------------- 10 (one of the greatest films)
A Bug's Life -------------------- N/A
Toy Story 2 --------------------- 8 (not as good as its predecessor)
Monsters Inc -------------------- 9 (Another timeless film)
Finding Nemo -------------------- 10 (nothing needs to be said)
The Incredibles ----------------- 10 (almost the best superhero film)
Cars ---------------------------- N/A
Up ------------------------------ 8 (very good)
Cars 2 -------------------------- N/A
Ratatouille --------------------- 9 (excellent)
WALL-E -------------------------- 8 (didn't age well for me)
Brave --------------------------- 6 (most disappointing original unless I see Cars)
Monsters University ------------- 7 (not Pixar quality, but good enough)
Toy Story 3 --------------------- 7 (never got to like it for some reason)
Seen - 11/14
Average - 8.36
Ghibli
Spirited Away ------------------- 10 (very very very engaging)
Kiki's Delivery Service --------- 8 (also very good)
Pom Poko------------------------- 7 (got a bit boring towards the end)
Porco Rosso --------------------- 9 (very good, yet again)
Princess Mononoke --------------- 9 (excellent)
Arrietty ------------------------ 7 (would've been 9 if a certain character was absent)
Castle in the Sky --------------- 8 (nice)
Ponyo --------------------------- 7 (okay, sort of)
My Neighbour Totoro ------------- 11!! (among my top films of all time)
Whisper of the Heart ------------ N/A Grave of the Fireflies ---------- 10 (very very emotional)
Tales of Earthsea --------------- N/A
Howl's Moving Castle ------------ 8 (storytelling was a bit of a mess, still very good)
From Up on Poppy Hill ----------- N/A
Seen - 11/14
Average - 8.54
OP didn't include Naussica, I'd given it a 7, average would be 8.42, a bit above Pixar.