Hi,
I recently watched a show on the history of pizza. They said that frozen pizza was hard to get just right, that there was too much moister in it and that it made a soggy crust. There are one of two things you can try, pre bake your crust, or do what all the frozen pizza giants do, use baking powder, by using baking powder you get a rise while baking, and it freezes well .
Hope this helps.