You've got the basic jist of it. There is some difference in intent, and differences in goals. A drag queen might do many of the things a transwoman does -- at the professional level many drag queens have breast implants and take other measures to feminize their appearance, and they might live full-time as women. OTOH many drag queens are fine with it if no one mistakes them for a woman ever. At heart they still see themselves as men, just with an interesting fashion sense. :)