how long does Mountain lion take to download?

Its Showing me 72 Hours and 40 Minutes for the past half hour !

So i am downloading Mountain Lion for the sole purpose of playing a video game that requirs Mac OS X 10.7.4 or later, and I think i have Mac OS X 6. Does that mean when this download is complete i have to buy a seperate thing to download it to 7.4??

It depends on your internet connection. If you want to check your internet speed look at this website: http://www.speedtest.net/. I have a 7 mbps connection and it took about 32 minutes.