Cant move pages from one document to another

I assume that you are saying that the option to move pages to a new document is there in the Move Pages command from the Pages Panel drop-down and the other document is showing but is either greyed out or the process won’t complete. Moving pages in this manner is usually a simple matter, even with different page sizes, so it may be that deleting your preference file might be necessary.

To do so:

With InDesign closed launch a Finder Window in column view and click on your home folder. With the Option Key pressed choose Library from the Finder Go Menu. Within the Library folder find the following two files and delete them: “Adobe InDesign” and “com.adobe.InDesign.plist”. When InDesign is next launched it will create new preference files and the program will be restored to its defaults.

After you’ve reset up the program (make sure that no document window is open) to your liking, it is a really good idea to create copies of your personalized “mint” preference files (make sure that you quit the program before copying them—that finalizes your customization) and use them in the future to replace any corrupt versions you may need to delete.