select from two open docs

Can someone help? CS4 on a PC. This is probably easy, but I seem to be stuck.

I have 2 open photos A & B.
I want to open photo C
Paste photo A onto top left of C
Paste image number of A on C under A
Close A with out saving
Paste Photo B onto top right of C
Paste image number of B on C under A
Close B without saving.

Image C is always the same, A and B will always be open, but are never the same image number. I think I can figure out the rest of what I want to do from other scripts I have done.

This is basically to put 2 5x7 pictures on an 8x12 with their image numbers for event printing. I've been doing it manually and it takes forever. I have done this with 8x10's and it works really great. Image C has my info already on it . Saves to 3 different places, automatically prints, and closes everything ready for the next pic. I'm having problems dealing with 2 open pics and how to handle them.

Thanks.