don't really have a personal favorite Anime opening but i'm just gonna put a few i love.
Naruto Shippuden opening 6 (its impossible to find an unedited version of this opeing Youtube and also RIP Pervy Sage)
One Piece Opening 13 One Day (this one sure does bring in a ton of the feels espically if you know how the marineford arc ends)
Code Geass opening 5 (easily my favorite opening to my favorite Anime)
Tokyo Ghoul season 1 opening (not much to say about this one except that i haven't seen any episode of season 2 yet or haven't read the Manga yet)
all 4 Jojo's Bizarre Adventure openings (cause its Jojo damn it)