I polled my family and here are the answers I received:
My other DIL, Jessica, likes good ol' Hershey's chocolate syrup! My husband feels the same.
Lindsey has similar taste to me and chose Hot Fudge Sauce first, but when I told her that she had to choose something different from me, she followed up with strawberries and whipped cream! I like both of those as well, so I think we would have a lot of fun planning an Ice Cream Sundae Party and choosing all of the things that we love!