Do you want this menu on the layout or part of the menus you see across the top of the screen? (Where you see Format, Records, Scripts, etc.)
You can't setup a sub menu for value list formatted fields on the layout, though you can set up a conditional value list that has a similar function.
You cannot create sub-menus in pop-up menus that are attached to the layout fields. You can have a plug-in that does this. If you have FM Advanced you can also redefine the applications menus; there you can add a menu of reports with all submenus you want.
To me it seems somewhat difficult to print a report with just a single command. Most reports have options to configure, quite a few sometimes. I usually display a pop-up window that lists reports and their options and allows to either print or preview:
Without Filemaker Advanced, you can still create a folder named "Reports" in the scripts menu and place the individual "report" scripts inside it.
Thanks for your posts. I actually figured out the whole custom menu and sub menu thing a little while after I submitted my post and it works just the way I wanted it to. Thank you for responding so quickly.