Kathy Garver, the voice of Firestar on Spider-Man and His Amazing Friends (1981), provides the voice for the lizard woman Gila.
While not exactly a two-parter, this episode is a continuation of Partners in Danger Chapter 9: The Haunting of Mary Jane (1997), taking place right after the previous episode ended.
While not changing the entire world into Lizards as he mentioned in Night of the Lizard (1994), Dr. Connors unknowingly let neogenic fluid go down the drain after experiments to permanently re-grown his arm. This actually fulfilled his alter ego's dream of a world of reptiles with a bunch of lizards mutated into humanoid form though the fluid that went down the drain.
In this episode Peter Parker asks Mary Jane Watson to marry him after revealing to her that he's Spider-Man, she accepts his proposal.