no Tony didnt wanna fuck his sister..i never understood why people said that..even in the scene where she first walks in his office saying"you cant stand for another man to be touching me ..so you want me tony huh?)
Tony replies with a confused look on his face"what you talking?!!

she was the only pure thing in his life remeber and its his bloody little sister of course he loved her..

as for elvira..well i think tony loved her to the extent he could love a woman..i dont think he knew how to express himself properly either..just my thoughts