crowd levels
February used to be a great time to go, several of the weeks in February typically used to have the lowest park attendance of any month. HOWEVER, in recent years this has changed. I am going down Feb 7-11 and I was unable to even get a cast memeber discount on a hotel because of the high volume of reservations. Also Disney has begun to add things in the month of February such as the National High School Cheerleading Competition, which will be going on while you are there. So to answer your question, it won't be as busy at a holiday or summertime but you also won't have "run" of the park either. Expect moderate crowds with moderate wait times for popular rides.