To reduce megabytes, you first have to reduce resolution of the image. The resolution is probably somewhere at 3450x2800 or something. That's extremely large for web viewing. Go to Image > Resize > Image Size in Photoshop Elements. Now for the Width type something like 600 or 500 pixels, and the Height should automatically change. (If it does not change automatically, make sure that "Constrain Proportions" is checked.) Press OK, then go to File > Save As and save as a .JPG file. Now it should ask you the quality you want to save it as, and it should give you an estimate of the ending total size of the file to the right under OK or CANCEL or somewhere on the right...Might be in the middle bottom too. Just look around for small numbers like "200kb" or something. Okay so now click on the bar and bring it down to about 6 or 7. You will lose some quality, but it will drastically reduce your physical size.
Test that out and let us know how it went.