Yes, yes, multi-touch is amazing. Unless you’re my grandmother, and you’re just trying to use the mouse that came with the computer to get your email. She was constantly getting frustrated with how Magic Mouse responded to her touch rather than her click, so I disabled the multi-touch features.
My grandmother had the exact same problem. He has a list of Terminal commands to disable scrolling entirely. I think you can turn off inertial scrolling in the Accessibility pref pane, and you can turn off gestures in the Mouse pref pane, but there’s no checkbox for scrolling itself.