Displaying listings from another application

First day here and having fun so far -- great resource!

I'm not new to creating sites but I'm new to WP. I've searched but wasn't able to find info on what I would think was a common enough situation:

I'm also running a directory application on my server, PhpMydirectory, and would like to display some of the restaurant listing data on my site using the Studio template. What is the best way to do that? My directory app already displays these listings on its home page, can I simply use the PHP code that displays that data? If so, can I place that in a widget or one of the other content containers in the Studio template? or do I need to edit template?

Thanks in advance