To mod note: I can't speak for everybody's computers but from my own experience full screen does have a noticable speed effect. My first attempt was recorded in windowed mode and this one is on full screen. You can see the difference especially during the minigames, but it's also overall a bit more responsive on full screen that it is on windowed. Since I'm talking just from my own experience, your results may vary. I'm on 12th gen i7 and rtx 3070 if that's somehow useful information if you wanna look in to it more.