Considering Dish already provides a list of recordings by pre-set genres, one of those being MOVIES, Dish probably feels they have that covered. From their point of view they would say to use the pre-defined default Folders by Genres view. If a program is NOT News/Business, Sports, Movies, Education, or Music/Arts, then all you have to do is select the Series/Special folder to see all the remaining programs, and that is the bulk of the programming on Dish. That will effectively achieve what you want with minimum fuss and WITHOUT REDUNDANCY. However, you're perfectly free to use one of your 5 allotted Custom Folders as you own "generic" catch all folder that would not include MOVIES.
Create your Custom "My TV Shows" folder. Now, each time you create a timer, set the timers to automatically send the show to "My TV Shows" Folder. For movies, don't select a folder to send it to when creating the timer. Further, don't bother with making a Custom MOVIES folder because they are already organized in the Folders by Genres view and have their own folder there automatically and will display only movies in that folder. This takes the place of having to create a Custom MOVIES folder. Dish already does that for you automatically from the Folders by Genre selection. If you forget to set the timer to send the show to your custom folder, you can move it from any of the other Folder views to your custom folder. At least that's what I would do and it would seem to achieve exactly what I thing your trying to do.