Ontop of the comments regarding the windows, what are you projecting onto? White walls will work, but won't be as bright and clear as a projector screen.
How well it all works depends on your laptop. Most modern laptops will work most video fine, heck, most will work happily enough with HD video. A friend of mine used to have an HD projector setup and it was pretty sweet.
EB Musicman/Ibanez/Ampeg/Peavey/Marshall/Tech 21