The only method that I know is to limit your found set to a single record so that there are no records to "scroll through" with the wheel. Of course, this changes the behavior of other standard controls on your layout and requires quite a bit of extra scripting to regain the ability to work with a found set of records (maintained in a different window or a layout based on a different table occurrence) while you current layout and window only has a found set of 1...
Hope to have a new version of FM with a different behavior for the scroll of the mouse. Everyone is complaining about this, I do not know why FM has not changed this. It is really annoying to move from records with the scroll and is not a natural behavior for it. Whenever I am teaching someone how to use a DB the first problem is to explain that the mouse scroll will change the records :s