The "metadata name" is the name that will be presented on the JPG store? And what is the "title name?"

Metadata Name:

This is the name of the Trait in the properties list, for example: if you have a trait called "happy-something.png", you can set its metadata name to "Happy".

Title Name: ( Will no longer exist in newest version )

By default each NFT will have the name "Project Name #1", "Project Name #2", "Project Name #5000", etc.

If you want each NFT to have a customized name (like Mr. Green or Clayton Bigsby) you can set this for each trait - the final name of the NFT will be the combination of all Title Names that were used in the NFT.