Notes express a melodic pattern. Each note is like a letter, putting the notes together makes a musical "word" So one note may represent just a small part of a lyrical phrase or the whole phrase itself.
Your question doesn't make a whole lot of sense to me, but when I sing anything choral, I highlight in yellow the words and my part. I don't know if that helps any. (Unfortunately, I've never had the nerve to audition for a real opera.)
you can go to the options menu and there is something that can help you there or! it depens on the difficulty your playing easy makes it big medium the same hard and expert is kinda small
It might be because of your video card interfering with your sound card. Try to move the two cards as far away from each other as possible in the correct slots.