There are many English - Spanish translation software with pictures for preschoolers, but personally, I recommend you try 8 in 1 English Dictionary. It is a commercial application developed by English Computerized Learning Incorporated and beside Spanish, it supports Arabic, Chinese (traditional and simplified), French, German, Hindi, Japanese, Korean, Polish, Portuguese, Russian, and Vietnamese. Also, you can test it free of charge using the demo from the official web page.
