Actually my favourite ending was "BIG"
At first i hated it, and rightly so!! It was flipping hard to understand. Like pretty much everyone else that saw it, i was really annoyed!! Until i did some research and watched it a DOZEN more times to work out what the heck happened. After i understood, i loved it !! Perfect ending :)
Worst ending... "Marry him if you dare".... don't even get me started..