Ok, so I might have figured it out. I realized that the .em file that is a menu template is a bunch of video and psd files linked into one file. So, I searched my hard drive for the name of the menu (NTSC_Ribbon) and found a file with the extension .m2v. That is the video file of the background only. I couldn’t import it into Final Cut, but Premiere let me import it. I then found the .psd file of the still background image for the menu.
I created a background for the menu. Then I exported it as a .m2v file (which is the MPEG2-DVD setting on Premiere). I then imported it into my project as an asset. Then, I replaced the video of the menu with my video. I did this 2 different ways. You can drag it onto your menu while holding the option(alt) key. The other way is to click on the menu and go to the properties tab on the right. Link the video to the imported background.
Now, it is all fixed! Thanks for all your help!