Guess I should bump this once, before it disappears. Voting's gone about as expected - DKC 2 was definitely my favorite, and it was one of the first games I fully completed. Funny story there, I once rented it years before I could buy it and got stuck on the lava level with the hot air balloons because child me didn't understand that you had to stand on the ballons and use the d-pad to move them (I kept trying to jump from them instead and, well, fell in lava).
As for DKC's esoteric secrets, here's the most egregious example:
https://m.youtube.com/watch?v=sqgqj6ZQRJw
It was evidently not only a bonus stage hidden inside another bonus stage, you had to intentionally get the worst item as the reward, which then gave you a barrel instead of said item,
then
you had to hold said barrel and jump into the exit. If you walked to it, you instead left the bonus stage and went back to the regular level. How anyone ever figured this out, I don't know.
Also, if anyone's curious and hasn't seen it, this is the promo VHS I was referring to:
https://m.youtube.com/watch?v=Wgw-TEWuCQc