[ale] Converting size with Gimp

[Chris Fowler]

I'm trying to use convert to add a white border around my 4.0MP images. 
I then use GIMP to write a date on that border.

When I take to Sam's to print it wants to crop the image to 4x6, 5x7, or
8x10.  This cuts off the top half and bottom half of the picture.  I do
not care about losing part of the picture I do not want to lose the
bottom and top border.  Is there a way I can use GIMP to crop the image
to a 4x6 size without it trying to size the image smaller.  I like the 
size of the image being big because I want to make sure there is enough
data there to print a nice image.

I'm trying to come up with a process to add a border and data to an
image before I print them.  I do not like the date on the actual image
so I do not allow my camera to create one.  I like the date on the white
border I've created.  Now If I can only figure out the perfect font and
how to position the date text in the exact center of the white border.

Thanks for the help,
Chris