Windows 7: Cannot enable smooth mouse scroll in Windows Explorer Navigation Pane

Not sure if this is due to my hardware or some setting in Windows 7. I have Win 7 Pro x64 on a Sony Vaio ZPCZ11. Using the MS Natural Wireless Laser Mouse 7000. In the file view of Windows File Explorer, if I click in the space and wheel scroll, everything works fine and the scrolling is smooth. But when I click in the Navigation Pane (Folder List) and try the same thing, it wants to scroll an entire page at a time. I cannot get the smooth mouse scrolling to work in this Pane! Any ideas how to fix this?

Well, if anyone cares, it appears that my scroll rate was set too high...even though it works well in certain apps and areas, it just goes too far in Windows Explorer. Set to a lower rate, it scrolls in the Nav Pane normally.