I think the best way to set this up would be with a "filtered portal"--That's a term you can research here for other examples/discussions on how to do this.
Define a "Notes" table with the following fields:
ID (number field)
Let's call your layout's table "Main" and set up a relationship between your two tables like this:
Main::ID = Notes::ID AND
Main::NoteType = Notes::Type
Main::ID would be defined as an auto-entered serial number (Double-click the field's definition in Manage | Database | Fields)
Main::NoteType is your radio button field.
Double click the line linking your two Table Occurrence boxes and select "Allow creation of records via this relationship" for the Notes table.
Now you can display your notes in a portal located beneath your radio button field. The radio button field acts as a filter showing only those records of the type you select and only for the current record. You can set up the portal with a scroll bar to display multiple notes in a category or just one such note. If you make it possible to see multiple notes, you'll even be able to shift-click your radio buttons to select more than one type and see all the notes from all the selected types.
Thank you so much for your help. I will try it out and do a bit of research on what you adviced me. Thanks!