This is the second (or third) time I'm stumbling over this, and I keep forgetting. Ugh, thank you.

Bravo. I have been pulling my hair out w/ a similar issue for the better part of a year. Never found it worthwhile to go through that config file manually; looks like there was a pretty contained fix after all!

See my answer to this question for an alternative workaround.

Actually, turns out you pretty much CAN uninstall the mouse drivers, which will both solve the problem and not cause any long-running issues. (Uninstalled Lenovo Mouse Suite from under Programs and Features and the scroll-wheel seems to be working just fine now)

Alternatively, for a more standard (and also more user-friendly) approach, open the start menu and type 'Adjust the appearance' into the search box. Next, open the first matching item in the expanding result list (named 'Adjust the appearance and performance of Windows') and you'll arrive at the exact same menu.