I got used to installing VN's just by the process of repetition by doing it hundreds of time and all I know is basic Kanji.
Left button is install and right button is cancel by the way on that screen.
Now that I(and you) know where your game is being installed you should just click the left button and let it do it's thing. Afterwards it'll give you an install completed message. Followed after a shortcut tickbox I think and just say yes to that.
I still have the files from before I unistalled the last one I'm guessing I should delete them?