If you are used to Mac OS X Lion “natural” scrolling behavior, you might be interested in to how to emulate such behavior in Windows.
There is a registry setting named FlipFlopWheel that does allow reversing the scrolling direction, both vertical and horizontal. The exact name of the registry key depends on the HID of the mouse devices and, in computers with multiple input devices, there might be multiple entries.
Look for a key under HKEY_LOCAL_MACHINE that is named like SYSTEMCurrentControlSetEnumHID????????Device Parameters. Change the value for FlipFlopWheel from 0 to 1 to reverse vertical scrolling. In Windows 8, there’s an additional FlipFlopHScroll that allows reversing horizontal scrolling.
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You state “there is a registry setting named FlipFlopWheel that does allow reversing the scrolling direction, both vertical and horizontal”; however, I have found that on Windows 7, changing that value only changes the direction of vertical scrolling; have you found otherwise? As you point out, Windows 8 has another registry setting for reversing horizontal scrolling (FlipFlopHScroll); I wish Windows 7 had that too! It seems like a huge miss to have implemented FlipFlopWheel without FlipFlopHScroll in Windows 7!
I added the FlipFlopHScroll registry key in Windows 7 and it horizontal scrolling works for me too now 🙂