I don't recall what my favorite ice creams flavors were as a child. I suspect I liked most of them. Even then, I liked chocolate and vanilla together, which is still one of my favorites.
As a younger adult once I tried Swensen's German Chocolate Cake ice cream I became quite addicted. I don't think Swensen's is still around, and I haven't had it in years, but it would still probably be my favorite.
(A quick check says that Swensen's is only available in San Francisco.)