You can't, but you can change to the Classic Start Menu.
Right-click the Start button
Choose Properties
Click The Classic Start menu radio button
Click Apply
Click the Customize button
Scroll down the Advanced Start menu options and check the option "Scroll Programs"
Click OK
Click OK
When you now go to "Programs" on the start menu (on the Classic menu it's not called "All Programs"), you''l get a single column of all your programs. If there are too many to fit, you'll see a little arrowhead at the bottom; mouse over it to scroll down, at which point a similar arrowhead will appear at the top, to allow you to scroll up.