when you have big hard drive sometime you forget what film is on drive when copy and you have 2 version same film not same quality it should have a menu the 2 film or choice winch version you want to play i always end up watching worst quality version! is it just me?
I am going to assume that you are using the Home Theater app? If so, then yes Zidoo does let you know the differences between the files.. if both titles were named the same, then both should show up under the Movie's title page with a default nomenclature of either A or B versions of that same movie are available..... when you highlight either version, the differences between them will show in the Media Info icons that pop up...
Using the Home Theater 5.0 App, when you click on the icon for the title there should be an overlay at the bottom of the page which shows the Path of the file. While that doesn't give you the file size or date it was included in the library, you should be able to figure out which file is which.