Under the Matrix Pages & Titles tab there is a checkbox labeled
Show folder name if no folder title entered.
How do I set a folder title?
The same way you do, no matter what skin you're using. Double-click the folder to open it, then enter the title you want on the right - see screenshot.
Also, on the main page under a folder thumbnail is the number of images. Is there a way to not display that?
Uncheck
Matrix > Captions > Thumbnails > Folder Thumbnails > Show count of files in folder.