The best thing about opera is that it is never in English anyways, so going to see one in Turkey is not as difficult as theater would be.
The Ankara opera house has a varied program and simultaneously puts on different operas. For January 2010, the schedule is:
Aida by Verdi: January 16 2010
Idomeneo by Mozart: January 20 2010
Viva la Mama by Donizetti: January 27, 30 2010
A Night in Venice by Strauss: January 18 2010