Don't know if when you double click on photos if they come up in infranview but if they don't start this program:
Then most of the time just do an File -> save AS
set the save as type to JPG and put the quality at 80-90 and pic some new name that you will recognize.
just bringing the picture quality down from 99 to 90% can reduce the file size ALLOT (sometimes 10 to 1).
If that is not enough goto image->resize/resample and reduce the size of the image by half (this will reduce the image size 75%)
