I have never noticed a line at the microwaves. But I think a pretty easy fix was stated above - if you see a line, finish the one you are on and let the other guests microwave what they need, and then go back to microwaving when they are finished. As for microwaving frozen dinners? I typically see mom's using it for infant needs and I think one person zapping a piece of pizza. I have never paid that close attention. If it is for dietary needs, you can ask to see if they can put one in your room. There will probably be a renting fee but it would be worth an ask.