I usually liked smart girls back then, like Inspector Gadget's Penny and Lisa Simpson.
I remember I didn't use to like Misty from Pokemon until that episode in Azure City when she put on that mermaid costume and it was like seeing her for first time.
As for the shameful non-anthropomorphic crush, Rita from Animaniacs' Rita & Runt always made me feel a bit flustered, especially whenever she sang.