Classically-trained mezzo soprano, here. I discovered opera in high school, when we all had to traipse to Music Hall, through some of the worst parts of the city. My first opera was a one-act thing, Schwanda the Bagpiper. Not the best in the world, but it infected me.
As a mezzo (next-highest female voice), I tend to favor Verdi, Puccini, Bizet, et al. Mozart usually wrote for the lyric sopranos (highest female voice, and the first to go), and Brahms for the contraltos (lowest official female voice, and longest lasting).
I had to learn "O Mio Babbino Caro" and "Habanera," studied the incomparable Maria Callas, and even discovered Cecilia Bartoli. Because of the piss-poor way I handle strong emotions, I could never really perform well. When I put my all into it, I couldn't get through the song. When I didn't, it was dull.
My favorite opera to date is Verdi's "La Traviata."
La Traviata: Addio del Passato - Maria Callas. Troppo bella per le parole
http://www.youtube.com/watch?v=QOUs0y_QpAEI'd like to see
Samson et Dalila - Camille Saint-Saens as well. Sang this aria in my senior recital (not nearly as well):
Samson et Dalila: Mon Coeur S'ouvre a ta voixhttp://www.youtube.com/watch?v=9piRiiZ0C4Q<edit>One more performance that brings tears of joy to my eyes:
Turandot: Nessun Dorma - as performed by...Aretha Franklin. I get goosebumps every time. She gives it a little soul, and sings it in English (American), but I still think Puccini would have liked it.</edit>
http://www.youtube.com/watch?v=LUvJZ26shqc