Move title below image in Views grid format with CSS
You could simply edit the "Teaser" view mode and place the title below the image using Display Suite Here are the instructions:


Download Display Suite and enable the "Display Suite" and "Display Suite UI" modules.
Go to admin/structure/types/manage/article/display/teaser where "article" is your content type.
In the "Layout for article in teaser" fieldset, select the "One column" layout and click Save.





You will now see a lot more fields, provided by the Display Suite module. One of those fields is the title field.





Now drag the title field up to the top, below the Image field, just like you requested. From what I understand from your question, you could remove the Body field as well.





All done! No custom theming required.