Is it that you have an upload limit in terms of KB for your images?
There are several ways to reduce the size of an image.
One is to actually reduce the image size - this will make the picture smaller and also reduce the file size
Another is to compress the picture more - this will reduce the file size.
Yet another is to reduce the number of colours.
All of these should be possible in Phot-Album, I would have thought.
To reduce the size of the image - look for a "Resize" in the menus.
To apply more conpression, resave the image in jpeg format (maybe it's already in jpeg format - that's OK) - in the "Save As" dialogue for jpgs, you will see a button for Options, or similar, which will allow you to apply more compression - more compression = smaller file.