How long should it take for Norton disk optimization to cancel and close?

Hi - I was prompted to optimize my disk (defrag?) by my Norton product. I let it run for about 15 minutes and decided to cancel the operation. I let it cancel for another 15 or 20 minutes and decided to just shut the computer down. It has been displaying the Shutting Down screen for at least 40 minutes, with the rotating icon. Is this normal or should I do a hard shutdown?