Question about displaying iso videos

I previously owned the WDTV Lite and had no issues going through the folders section and seeing large thumbnails of the movies I wanted to watch, which were saved in .jpg format.

I transferred a few movies into this, but have a few questions.

First, how can I access them from the “Video” menu instead of the folders section

And second, How can I see a larger thumbnail for the image just as in the WDTV lite. The thumbnails are half the size.

From the video tab just press the red button on the remote control to select the source and to change the view type press the yellow button.