Welcome to the forum.
It is most likely that the PAR (Pixel Aspect Ratio) of your PS Titles do not match your Project's Preset.
Tell us which Project Preset was used? That will be what you will use, back in PS. Under Image>Pixel Aspect Ratio will correct that. They just need to match.
One could also use Interpret Footage in PrE (Rt-click on your Title), but I would do this in PS myself.
Wow, easy fix. Thank you!
I love the "easy ones!"
As I do most of my major Titles in PS, this is something that I deal with every day.
Similar crops up in the Encore forum, with Menus created in PS and then used in the DVD. The PAR bites a lot of folk. Think that it was with CS, that PAR was added to PS. Because of the display, PS will pop up a warning window, should you Open the Title (or a Menu) back in PS. I leave this on (can be turned off), just so that I am always reminded to check my PAR.
I also use the New Image Preset for my Project, say the NTSC 720 x 480 standard 4:3, PAR = 0.9 w/ Guides, to do my Titles, and my Menus. That gets me started and shows the Action Safe Area plus the Title Safe Area of the screen.
Good luck, and happy editing,