I don't know about changing the horizontal scrolling to vertical but it is possible to bypass the new "home" screen and run Windows 8 from the desktop like in Windows 7. I had to get a new computer and Win 8 was the ony option for the laptop I wanted. I did not like the tiles and even went so far as to delete all the apps. I downloaded a program to put the "Start" button back on the desktop and the program boots up my computer to the desktop. I sometimes even forget it is Windows 8.
Sorry that this doesn't exactly answer your question, but if you have to upgrade and can't find a solution, there are ways around that whole screen entirely.