Haven't used Elements, although I use regular Photoshop.
For printing, I save my photos as TIFFs because that format has a decent compression feature.
For JPEGs intended for the Web, I look at each photo individually, and increase the compression until just before the image quality starts to suffer. The ideal amount of compression is different for each photo. JPEG photos with lots of detail produce larger files than photos of, say, blue skies.
I hope this helps.