What you should try is....
a) Copy pictures from your Nokia 7650 to PC/lapptop using IrDA (or what ever)
b) Use PC Suite v5.01 to transfer picture to your 6610 using IrDA
This should work. I have noticed same kind of problems with some of the models. If you don't have this PC Suite 5.xx you can get it from:
There you can found for example applications like: Nokia application installer, Nokia Image Converter, Nokia Content copier and Nokia PC Graphics/Composer etc. to use what ever content you are managing / distributing.