I believe what that above scantly-educated thing was trying to suggest was Rain-X Anti-Fog. I believe you have to rub it on, wait till it dried then wipe it all off very good with a clean cloth.That may very well work because it should keep moisture from building up on the windsheild. No moisture, no ice.That is very strange - you should not have moisture building up like that inside your car. Are there any leaks anywhere? Sunroof?