Favorite classical composers?

in english we are currently studying the book Maestro. It has a lot of references to great composers, such as Wagner, Mozart, Liszt and Chopin, compared to those in the like of Gilbert and Sullivan. As unfortunate as it is, i don't know much about classical music etc, so i was wondering if i could get any ones thoughts on their favorite composers and their greatest works? and why exactly you love them? any answers would be greatly appreciated, thankyou :)